Cambridge International Examinations
Cambridge International Examinations
               CANDIDATE
               NAME
               CENTRE                                                                CANDIDATE
*8927566197*
NUMBER NUMBER
               MATHEMATICS                                                                                           9709/31
               Paper 3 Pure Mathematics 3 (P3)                                                     October/November 2017
                                                                                                            1 hour 45 minutes
               Candidates answer on the Question Paper.
               Additional Materials:     List of Formulae (MF9)
               Write your Centre number, candidate number and name in the spaces at the top of this page.
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               The number of marks is given in brackets [ ] at the end of each question or part question.
               The total number of marks for this paper is 75.
               JC17 11_9709_31/FP
               © UCLES 2017                                                                                        [Turn over
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2    Two variable quantities x and y are believed to satisfy an equation of the form y = C ax , where C and
     a are constants. An experiment produced four pairs of values of x and y. The table below gives the
     corresponding values of x and ln y.
     By plotting ln y against x for these four pairs of values and drawing a suitable straight line, estimate
     the values of C and a. Give your answers correct to 2 significant figures.                           [5]
ln y
                                                                                                                               x
                                        0                      1                2                   3                  4
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Two iterative formulae, A and B, derived from this equation are as follows:
                                                                 xn+1 = 3xn + 7 3 ,
                                                                                          1
                                                                                                                  (A)
                                                                            xn3 − 7
                                                                 xn+1 =             .                             (B)
                                                                               3
     Each formula is used with initial value x1 = 2.5.
      (ii) Show that one of these formulae produces a sequence which fails to converge, and use the other
           formula to calculate ! correct to 2 decimal places. Give the result of each iteration to 4 decimal
           places.                                                                                        [4]
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4 (i) Prove the identity tan 45Å + x + tan 45Å − x  2 sec 2x. [4]
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(ii) Hence sketch the graph of y = tan 45Å + x + tan 45Å − x for 0Å ≤ x ≤ 90Å. [3]
                            dy     8x3 + y3
       (i) Show that           =−            .                                                                                                                [4]
                            dx    3xy2 + 4y3
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      (ii) Hence show that there are two points on the curve at which the tangent is parallel to the x-axis
           and find the coordinates of these points.                                                    [4]
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7    (a) The complex number u is given by u = 8 − 15i. Showing all necessary working, find the two
         square roots of u. Give answers in the form a + ib, where the numbers a and b are real and exact.
                                                                                                       [5]
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     (b) On an Argand diagram, shade the region whose points represent complex numbers satisfying
         both the inequalities  z − 2 − i ≤ 2 and 0 ≤ arg z − i ≤ 14 0.                    [4]
                     4x2 + 9x − 8
8    Let f x =                     .
                     x + 2 2x − 1
                                                           B     C
       (i) Express f x in the form A +                       +       .                                                                                       [4]
                                                         x + 2 2x − 1
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9
                                        y
                                                 R
                                                                                                                              x
                                     O                     2
                                                                     − 12 x
     The diagram shows the curve y = 1 + x2 e                                for x ≥ 0. The shaded region R is enclosed by the curve,
     the x-axis and the lines x = 0 and x = 2.
(i) Find the exact values of the x-coordinates of the stationary points of the curve. [4]
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                                                                                          42
      (ii) Show that the exact value of the area of R is 18 −                                .                                                                [5]
                                                                                           e
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(ii) Calculate the acute angle between the directions of the lines. [3]
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     (iii) Find the equation of the plane which passes through the point 3, −2, −1 and which is parallel
           to both l and m. Give your answer in the form ax + by + cz = d .                          [5]
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