Ia 1
Ia 1
1. FUNCTIONS
1.    i). if f(x) = 3x - 2,         x 3
                      2
                  = x - 2, - 2       x 2.
                  = 2x + 1          x < - 3, then find f(4), f(2.5), f(- 2), f(- 4), f(0), f(- 7) [March 2014]
                      π π π π
      ii).if A = 0, , , ,     and f : A B is a surjection defined by f(x) = cos x then find B.
                      6 4 3 2
                                          [May 2017AP 2017TS 2015AP 2015TS March 2017TS 2016AP]
      iii).If A =                   and f : A B is a surjection defined by f(x) = x2 + x + 1, then find B.
                      2, 1,0,1, 2
                            [March 2019AP 2017AP 2016TS May 2019AP 2016AP 2016TS 2014]
2.    if f = {(1,2),(2,- 3),(3,- 1)} then find
      i).2f                                                               [March 2020AP 2012]
           2
      ii).f                                                               [March 2020AP]
      iii).2 + f                                                          [March 2012]
3.    If f = {(4,5),(5,6),(6,- 4)} and g = {(4,-4),(6,5),(8,5)} then find
      i).f + g                                                             [March 2017TS]
      ii).f - g                                                                    [March
      2017TS] iii).f.g                                                             [March
      2017TS]
4.    If f(x) = 2, g(x) = x2, h(x) = 2x.then find (fogoh)(x)                    [March 2017TS]
                  x 1
5.    If f(x) =       where x        1 find (fofofof)(x)                       [March 2005]
                  x 1
                                         2
12.   If f :R R is defined by f(x) = 1 2x, then prove that f(tan ) = cos 2                   [March 2020TS]
                                           1 x
                                                                                      1 x                                         2x
 13.    If f : R-{ 1} R is defined by f(x) = log
                                                                                      1 x , then show that f                           2
                                                                                                                                           = 2 f(x)
                                                                                                                                  1 x
                                                                                                                                       [May 2018AP]
                                y                           y
14.    If f(y) =                       2
                                            , g(y) =                2
                                                                        then show that (fog)(y) = y                                     [May 2016TS]
                               1 y                      1 y
15.    Find the domain of the following functions.
                1                                                                                                     1
       i).            .                           [March 2019TS]                                 ii).         2
             6x x 2 5                                                                                    (x           1)(x 3)
                                                                                        [May 2018AP 2017AP 2014 March 2020TS 2014]
16.    Find the domain of the following functions.
       i). 2 2              [June 2004]                                                          ii). 4x x2                     [March 18TS May 2019AP]
              a        x
       iii). x2 25                                [May 2018AP 2015AP March 2018AP]
                   1                                                                                          1
       iv).                                       [May 2013]                                     v).              2       2            [March 2015AP]
                  1 x
                           2                                                                                  x a
17.    Find the domain of the function log(x2 - 4x + 3)                                                                        [March 2016TS May 2016AP]
18.    Find the domain of the following functions
                                                                                             2 x             2 x
                  3 x           3 x               [March 2007]                        ii).                                             [May 2015TS]
       i).                 x                                                                         x
19. Find the domain and range of the                                                   9 x
                                                                                             2                                    [March 2017AP 2015TS]
function
                                                                            2x 1
20.    If f : R R is defined by f(x) =                                           is injection or surjection justify your answers ?
                                                                             3
                                                                                                                                              [March 2015TS]
                               1        2             3 8
       ii).if A = 3 4 , B = 7 2 and 2X+A = B then find X. [March 2015AP 2013 2011 May 2012]
                   1 2 3                          3 2 1
3.     If A =      3 2 1
                                        ,B=       1 2 3
                                                            find 3B - 2A                                                               [March 2019TS 2012]
                                                                                  x 3 2y 8               5             2
4.     i).Find the values of x, y, z and a                                                       =
If                                                                              z 2      6               2        a 4
                                                            1           2        1/ 2
      iii). Find the trace of                               0            1        2     [May 2015TS]
                                                           1/2          2         1
                                                                                                               1
6.    Construct a 3 2 matrix whose elements are defined by aij =2 i 3j [March 2017AP 2015TS]
                                       i       0
      7.       Find A2 if0 A i=                                                                                               [March 2016AP]
3 0 0
8.    If A =    0 3 0
                                   , then find A4                                                                   [May 2017TS March 2020TS]
                0 0 3
                2 4
9.    If A =    1 K
                              and A                2   = O find k.                              [May 2016TS 2011 March 2018TS 2017AP 2014]
10.   i). Define Symmetric Matrix give an example                     [May 2013 March 2018AP]
                                                    T
      ii). If A is a square matrix then show that AA is a symmetric matrix      [March 2015AP]
      iii). Define Skew Symmetric Matrix give an example                   [May 2017AP 2017TS]
                      2        4
11.   i).If A =       5       3
                                   then find A+AT and A.AT                                                         [May 2019AP 2018AP 2015AP]
                                                                    1 2
                      2 1 0
      ii).If A =      3 4 5
                                               ,B=                  4 3          , then find A+ BT                                [May 2008]
                                                                    1 5
                          2 1
                                                           2 3 1
      iii).if A =         5    0       ,B=                 4        0 2          then find 3BT- A                                [March 2010]
                              1 4
                      1        5           3                        2       1 0
      iv).If A =      2        4           0   ,B=                  0       2 5       then find 3A - 4BT                          [May 2013]
                          3        1       5                        1        2    0
                1 2
12.    If A =                 then find A.A T                                                                                 [March 2017TS]
                  0
                  2       0 1                           1 1 0
13.   If A =    1 1 5
                                   ,B=                 0 1    2                  then find (ABT T)                    [March 2019TS May 2012]
1 2 3
                                                   2        5 6
14.   Find x If the matrix                                                  is a symmetric matrix.         [March 2016AP May 2018TS 2015TS]
                                                   3        x 7
0 2 1
                                                       2 0  2
15.   Find x, if the matrix                                    is                 a skew symmetric matrix            [May 2014 2013 May 2011]
                                                         1 x 0
                cos     sin
      iii). sin         cos
                              [March 2013]
                           1           1  3 3
11.   prove that cos252      - sin 2
                                     22 =                                                    [May 2019AP]
                           2           2   4 2
12.   i). Prove that tan700 - tan200 = 2.tan50                                              [May 2016AP]
      ii). Find the value of tan200 + tan400 +                3 tan200 tan400.             [March 2020TS]
                   cos9 sin 9
13.   Prove that              = cot36            [May 2017AP 2015AP 2015TS March 2018TS 2015AP 2011]
                   cos9 sin 9
                                              5 1
14.   Prove that sin2420 - sin2120 =                                                           [Sept 2000]
                                              8
14.   Prove that       i). sin500 - sin700 + sin100 = 0                                    [March 2018TS]
                       ii). sin340+cos640 - cos40 = 0                                          [May 2014]
15.   Prove that       i). 4(sin240+cos60) = 15 3                                              [July 2001]
                                                  3       5
                       ii). cos480 cos120 =           8                                    [March 2017TS]
16.   Find the period of      i).f(x) = cos(3x + 5) + 7                                     [May 2017TS]
                                                      4x 9
                              ii).f(x) = cos          5
                                                                                            [March 2014]
     QNO : 11 IN IPE
     3. MATRICES
                  1 0                      0 1
1.   If I =   0    1
                      and      E=         0 0
                                                 then show that (aI+bE) 3 = a3I+3a 2bE.
                                                                                     [May 2016TS March 2016TS 2015AP]
                       π                  cos2 θ                     cosθ.sinθ        2
                                                                                   cos φ      cosφsin φ
2.   If θ - φ =          then show that                                                                   = 0.
                       2                cosθ.sin θ
                                                                         2
                                                                       sin θ     cos φsin φ    sin2 φ
                    1      2     1
     ii).If A =     0      1     1       then find A3 - 3A2 - A - 3I                                      [March 2019TS 2011]
                    3      1 1
4.   Prove that every square matrix can be uniquely expressed as a sum of a symmetric matrix
     and skew symmetric matrix.                                                       [March
     2003]
                  cosα         sin α
5.   If A =                               then show that A AT = ATA = I.                                   [March 2020AP 2007]
                   sin α       cosα
                                                    1        2
                   2     1      2
6.   i).If A =     1     3      4
                                     and B =        3       0    then verify that (AB) = B A .                     [March 2013]
                                                        5
                       7        2
                                                2       1
     ii).If A =    1       2        ,B=         4       2   then find ABT and BAT.                             [March 2018AP]
                       5                       1    0
             1 2 1                                                     a 0 0
     iv).    3 2 3         [March 2017TS 2012] v). 0 b 0 [March 2006]
             1 1 2                                                     0 0 c
                       1    2       2
8.   i).If A =     2       1        2       , then show that Adj A = 3AT and hence find A-1.                    [March 2019AP]
                   2       2        1
                       1 2              2
     ii).If 3A =       2 1              2    then show that A-1 = AT                         [May 2018TS 2012 March 2014]
                        2 2             1
     QNO : 12 IN IPE
     4.ADDITION OF VECTORS
1.   If a,b,c are non coplanar vectors, then show that the following points are coplanar.
     i). 6a+2b-c, 2a-b+3c, -a+2b-4c, -12a-b-3c           [May 2019AP 2015AP March 2015TS]
     ii).-a+4b-3c, 3a+2b-5c, -3a+8b-5c, -3a+2b+c
                                               [March 18TS 18AP 17AP May 18TS 17AP 16TS]
     iii). 4i+5j+k, -j-k, 3i+9j+4k, and - 4i+4j+4k                                 [March 2014]
2.   Find if the points whose position vectors are coplanar
     i). 3i-2j-k, 2i+3j-4k, -i+j+2k, 4i+5j+ k            [May 2015TS March 2020AP 2020TS]
     ii). A(3,2,1), B(4, ,5), C(4,2,-2) D(6,5,-1)                               [March 2016TS]
3.   If ABCDEF is a regular hexagon, and O is its centre, then prove that
     AB+AC+AD+AE+AF = 3AD = 6 AO                     [May 18AP 17TS 16AP March 16AP
     15TS]
     QNO : 13 IN IPE
     5. PRODUCT OF VECTORS
1    Find the angles made by the line segment joining the points (1,-3,2) and (3,-5,1) with the
     coordinate axes.                                                            [March 2007 2006]
2.   If AB = 3i-2j+2k and AD = i-2k represent adjacent sides of a parallelogramABCD. Find
     the angle between the diagonals.                                                       [May
     2018TS]
3.   Show that the points (5,-1,1), (7,-4,7), (1,-6,10), and (-1, -3,4) are the vertices of a rhombus.
                                                                                        [March 2013]
4.   i). If a = 13, b = 5, and a.b = 60, then find a b                                                     [March 2020TS]
     ii). If a+b+c = 0, a = 3, b = 5, c = 7 then find the angle between a and b. [May 2019AP]
5.   Find the angle between the planes r.(2i-j+2k) = 3, r.(3i+6j+2k) = 4.
[May 2018TS March 2020AP 2020TS 2015TS]
6.    Angle in a semicircle is a right angle.                                            [May 2013]
7.    Find the area of the triangle with vertices (1,2,3),(2,3,1),(3,1,2).             [March 2014]
8.    Find the unit vector perpendicular to the plane generatedby a, b if
      i). a = i+j+k, b = 2i+j+3k                                                        [June 2002]
      ii). a = 4i+3j-k, b = 2i-6j-3k.                                                   [May 2009]
9.    If a = 2i+3j+4k, b = i+j-k, c = i-j+k then compute a (b c) and verify that it is perpendicular
      to a.                                                    [May 2019TS 2017TS]
                   1             1
3.    If sin = 10 , sin = 5 and , are acute show that + = 45 . 0             [May 2017TS]
4.    If 0<A<B< /4, sin(A+B) = 24/25, cos(A-B) = 4/5, find the value of tan2A [March 2015TS]
5.    i).If A+B = 45, prove that (1+tanA)(1+tanB) = 2                 [May 2011 March2016TS]
                                            cot A    cot B
      ii).If A + B = 225 prove that               .        = 1                              [May 2008]
                                           1 cot A 1 cot B   2
                        1            3
6.    i). Prove that sin10 -       =4                                 [May 2016TS March 2018TS 2016AP]
                             cos10
      ii). Prove that 3 csc20 - sec20 = 4                                              [March 2017AP]
7.    Prove that i). cotA+tanA = 2 csc2A,
                 ii). cotA-tanA = 2 cot2A                                      [May 2018AP March 2018]
8.    Prove that Tanθ +2 Tan2θ +4 Tan4θ +8 Cot8θ = Cotθ                                 [March 2019AP]
9.    Prove that
                                             1                                 π     2π   3π     4π   3
      i).sinA sin(60+A) sin(60- A)           4
                                               sin3A and hence deduce that sin 9 sin 9 sin 9 sin 9 = 16
      =
      ii).cosθ cos(60+θ )cos(60-θ ) = 1 cos3θ and hence deduce that
                                                4
          π       2π     3π     4π   1
      cos cos        cos    cos    =                                                        [June 2003]
         9         9     9       9   16
                             π             3π         7π         9π       1
10.   Prove that (1+cos 10 )(1+cos 10 )(1+cos 10 )(1+cos 10 ) = 16
                                                    [May 2015AP 2015TS March 2019TS 2019AP 2015AP]
11.   Prove that
              π        3π      5π    7π  3
      i). sin4 +sin4      +sin4 +sin4 =                                        [May 2013 March 2020AP]
              8         8       8      8   2
              π         3π           5π         7π    3
      ii). cos4 8+cos4 8 +cos4 8+cos4               =                             [May 2018TS 2016AP]
                                                  8     2
12.     Prove that
                                                     sin16A
        cosAcos2Acos4Acos8A =                                and hence deduce that cos 2π cos 4π cos8π cos16π = 1
                                                    16.sin A                           15     15     15    15 16
                                                                                    [May 2017AP 2012 March 2012]
                                  2π       4π         6π      1
13.     Prove that cos 7 cos 7 cos 7 = 8                                                                 [March 2020TS]
                                 π
14.     Prove that sin 5 sin 2π sin 3π sin 4π = 5                                                           [March 2013]
                              5      5      5   16
15.     Prove that the value of
                         cos A cos B                              n
                                                   sin A sin B
                     n                         +                      = 0 if n is odd and
                                                   cos A cosB
                         sin A sin B
                                                                                n A B
                                                                      = 2 cot           if n is even      [March 2016TS]
                                                                                   2
        QNO : 17 IN IPE
        10. PROPERTIES OFTRIANGLES
        In ABC, Show that
                         C             B
1.      i). b cos2           +c cos2       =s                                                            [March 2020TS]
                         2             2
                b2 c2            sin(B C)
        ii).         2       =                                                                           [March 2015AP]
                 a               sin(B C)
              1
2.      If      + 1 = 3    prove that C = 600                                                      [March 2019TS 2017TS]
             a c b c a b c
                  A     B    C ab bc ca s2
3.      i). Tan     +Tan +Tan                                                                                   [May 97]
                  2     2     2
=
                                     2
                     A     B    C
        ii). Cot       +Cot +Cot = s                                                                       [May 2016TS]
                     2     2    2
4.      i). If tan(A/2) = 5/6, tan(C/2) = 2/5, then prove that a,b,c are in A.P                                [June
2005]
        ii). If cot A/2,cot B/2,cot C/2 are in A.P then prove that that a,b,c are in A.P. [March
        2020AP]
5.      If a : b : c = 7 : 8 : 9 then prove that cosA : cosB : cosC = 14 : 11 : 6.                     [May 17AP 15AP 13]
6.   i).If cot(A/2) : cot(B/2) : cot(C/2) = 3 : 5 : 7 then prove that a : b : c = 6 : 5 : 4
                                                                                         [March 2017AP]
     ii).If the angles are in the ratio 1:5:6 then show that the ratio of its sides is
        3 -1: 3 +1: 2 2                                                                       [May 2007]
      1                               2 2    2
                 1              1
7.       2   +        2   + 12 + 2 = a b 2 c                                  [March 2019TS 2017TS]
     r           r1        r2   r3
     QNO : 18 IN IPE
     1. FUNCTIONS
1.   If f = {(4,5),(5,6),(6,- 4)} and g = {(4,-4),(6,5),(8,5)} then find
     i).f + g                                                                              [May 2018TS]
     ii).2f + 4g                                                                           [May 2018TS]
     iii).f+4                                                                              [May 2018TS]
     iv).f/g                                                                              [May 2018TS]
     v). f                                                                                [May 2018TS]
     vi). f                                                                               [May 2018TS]
     vii).f2                                                                              [May 2018TS]
     QNO : 19 IN IPE
     3.
     MATRICES
1.   Solve the equations by matrix inversion method.
     i).2x - y+3z = 9 , x+y+z = 6 , x – y+z = 2                                                  [March
     2016TS]
     ii).2x-y+3z = 8, - x+2y+z = 4, 3x+y-4z = 0                                [May 2015AP 2012]
     iii).3x+4y+5z = 18, 2x-y+8z = 13, 5x-2y+7z = 20                  [March 2019TS 2015AP 2013]
     iv).x+y+z = 1, 2x+2y+3z = 6, x+4y+9z = 3                                         [June 2003]
     iv).x+y+z = 9, 2x+5y+7z = 52, 2x+y - z = 0                               [March 2017AP May
     2011]
     QNO : 20 IN IPE
     3.
     MATRICES
1.   Solve the equations by Cramers Rule.
     i).x - y+3z = 5, 4x+2y - z = 0, - x+3y+z = 5.          [May 2018TS March 2019AP
     2015TS] ii).2x - y+3z = 9 , x+y+z = 6 , x – y+z = 2       [May 2013 March 2017TS
     2016AP] iii).2x - y+3z = 8, - x+2y+z = 4, 3x+y -4z = 0                    [March
     2018TS] iv).3x+4y+5z = 18, 2x-y+8z = 13, 5x-2y+7z = 20              [May 2017AP
     March 2012] v).x+y+z = 1, 2x+2y+3z = 6 , x+4y+9z = 3.         [May 2016TS March
     2020AP 2020TS]
     QNO : 21 IN IPE
     4.ADDITION OF VECTORS
1.   Find the point of intersection of the line r = 2a+b+t(b-c) with the plane
     r = a+ x(b+c) + y(a+2b-c) where a,b,c are non coplanar.                                       [May
     2013]
2.   i).If a,b,c are non coplanar vectors, then find the point of intersection the line
     passing through the points 2a+3b-c,3a+4b-2c with the line joining points a-2b+3c,
     a-6b+6c.
                                                                          [March 2019TS 2017AP]
     ii).If a,b,c are non coplanar show that the position vector of the point of intersection of
     the line passing through 6a-4b+4c, -4c and the line passing through -a-2b-3c, a+2b-5c is
     -4c.
                                                                         [March 2019AP 2016TS]
     iii).Find the vector equation of the plane which passes through the points 2i+4j+2k,
     2i+3j+5k and parallel to the vector 3i-2j+k.Also find the point where this plane meets the
     line joining the points 2i+j+3k and 4i- 2j+3k.                                    [March 2012]
3.   Find the vector equation of the plane passing through the points 4i-3j-k, 3i+7j-10k,
     2i+5j-7k.Show that the point i+2j-3k lies in this plane.                          [March 2013]
     QNO : 22 IN IPE
     5. PRODUCT OF VECTORS
1.   Prove that the smaller angle between any two diagonals of a cube is given by cos = 1/3.
                                                                                          [May 2017AP 2012 2011 March 2010]
2.   The altitudes of a triangle are concurrent.                                                   [May 2015AP March 2013]
3.   Find the unit vectors perpendicular to the plane determined by the points
     (1,2,3),(2,-1,1),(1,2,-4).                                                [March 2017AP]
4.   If a = b = 5, (a, b) = 450. then find the area of the triangle constructed with the vectors
     a-2b, 3a+2b as adjacent sides.                              [May 2015AP March 218AP]
5.   Let a = 4i+5j-k, b = i-4j+5k and c = 3i+j-k Find the vector which is perpendicular to
     both a and b and .c = 21                                                   [May 2018AP]
6.   Let a = 2i+j-2k, b = i+j. If c is a vector such that a.c = c , c a = 2 2 and the angle
     between a b and c is 30, then find the value of (a b) c .                                                [May 2015TS]
                                                                                              2           2
7.   For any two vectors a, b show that (1+ a 2)(1+ b 2) = 1 a.b + a b a b                                      [March 18TS]
     QNO : 23 IN IPE
     6. TRIGONOMETRIC RATIOSAND IDENTITIES
1.   If A+B+C = 1800 then prove that
     i). sin2A+sin2B+sin2C = 4sinA sinB sinC                                                                 [March 2008]
     ii). cos2A+cos2B+cos2C = -1- 4cosA cosB cosC                                        [March 2017AP May 2016TS 2015AP]
2.   If A+B+C = 1800 prove that
                                                 A           B           C
     i). cosA+cosB+cosC = 1+4 sin 2sin 2sin                               2                                   [March 2018AP]
                                                     A           B        C
     ii). cosA+cosB-cosC = -1+4 cos 2cos 2sin                                 2                               [March 2019TS]
                                             A       B           C
     iii). sinA+sinB+sinC = 4cos 2cos 2cos                           2
                                                                                                              [March 2020TS]
3.   In ABC prove that
            A       B          C                     A           B            C
     i).sin2 2 +sin2 2 -sin2    2   = 1-2cos 2 cos 2 sin 2                            [May 2018AP 2015TS 2012 March 2016AP]
                A       B           C                        A       B            C
     ii). cos2 2 +cos2 2 +cos2       2
                                            = 2+2sin 2 sin 2 sin                  2
                                                                                        [May 17TS 16AP March 15AP 15TS 12]
                A       B           C                    A           B        C
     iii). cos2 2 +cos2 2-cos2          2
                                            = 2cos 2 cos 2 sin                2
                                                                                                                 [June 2010]
4.   If A+B+C = 900 then prove that cos2A+cos2B+cos2C = 1+4sinA sinB sinC                                                 [March 2020AP]
5.   If A+B+C = 1800 prove that sin2 A+sin2 B-sin2C = 2sinA sinB cosC                                                       [May 2019AP]
6.   If A+B+C = 2700 prove that cos2A+cos2B+cos2C = 1-4sinAsinBsinC                                                         [March 2013]
7.   If A+B+C = 00 prove that sin2A+sin2B+sin2C = -4sinAsinBsinC                                                          [March 2019AP]
8.   In ABC prove that
               A            B             C                     π-A            π-B          π-C
     i). sin +sin +sin                        = 1+4sin                sin            sin                                 [March 2014 2011]
               2            2             2                      4              4            4
                A                   B               C
                                                                  π+A             π+B              π-C
     iv).cos           + cos             - cos          = 4cos             cos             cos                               [March 2005]
                2                   2               2              4               4                4
9.   If A+B+C= 2S Prove that
                                                                  S-A             S-B            C
     i). sin(S-A)+sin(S-B)+sinC = 4cos                                      cos            sin 2                          [March 2016TS]
                                                                            S-A            S-B             C
     ii). cos(S-A)+cos(S-B)+cosC = -1+4cos                                           cos             cos   2
                                                                                                                          [March 2017TS]
     iii). cos(S-A)+cos(S-B)+cos(S-C)+cosS = 4cos(A/2)cos(B/2)cos(C/2)                                                   [March 2018TS]
     QNO : 24 IN IPE
     10. PROPERTIES OFTRIANGLES
     In ABC
1.   Show that a3 cos(B-C)+b3 cos(C-A)+c3 cos(A-B) = 3abc                                                                    [March 2008]
                             a                               A
2.   i).If sinθ =               , prove that cosθ = 2 bc cos                                [May 2018TS 2014 March 2016AP 2012]
                            b c                     b c      2
                r1   r2     1 1
               r3          = -                                                                                                 [May 2014]
5.   Show that bc + ca + ab r 2R
                                A               B          C              r
6.   Show that cos2 2 +cos2 2+cos2                          2
                                                                 = 2+                                                       [May 2015TS]
                                                                          2R
7.   Show that
     i).r1 + r2 + r3 - r = 4R                                                       [March 2006]
     ii). r + r3+ r1 - r2 = 4R cosB                             [May 2018AP March 2020AP 2018AP
     2013] iii). r + r1+ r2 - r3 = 4R.cosC                                               [March
     2012] iv). if r 1: R : r = 2 : 5 : 12, prove that A = 90 .
                                                             0
                                                                                         [March
     2020TS]
     v). (r 1+r 2)sec2(C/2) = (r +r2 )sec
                                      3
                                          2
                                           (A/2) = (r +r3 )sec
                                                            1 (B/2)
                                                               2
                                                                                      [May 2019AP]
8.   If p1, p 2, p 3 are the lengths of the altitudes from the vertices of   ABC to the opposite
     sides then, prove that
           1  1 1     1                    1  1     1
                                                                                          2
                                                                                         (abc)    8
                                                                                                   3
     i).     + +
           p1 p2 p3
                    =
                      r                ii). + - 1 =                     iii). p1 p2 p3 =       =
                                           p1 p2 p3 r3                                    8R
                                                                                             3    abc
                                                                                           [March 2018TS]
9.   i).If a = 13, b = 14, c = 15, show that R = 65/8, r = 4, r1 = 21/2, r2 = 12, r3 = 14.
                          [March 2019AP 2016AP 2015AP 2014 May 2017TS 2017AP 2016 AP 2012]
     ii).If r1 = 8, r2 = 12, r3 = 24, show that a = 12, b = 16, c = 20.
                                                   [May 2018TS 2016TS 2015AP 2013 March 2017AP]
     iii).If r = 1, r1 = 2, r2 = 3, r3 = 6, show that a = 3, b = 4, c = 5.        [March 2016TS 2015TS]