rr +
oT, = 8 term |
+ Two = 100% term; etc.
«Ta = the nth term (the general term)
TF you know what Tn is, you can Find any
term in a pattern (a sequence).
Add (or subtract) the same number each
time.
Eg. -5; 0; 5; 10;.. or: 5; 2 -k -h
=—""” er we’
+5 +5 45 -3 -3 -3
Multiply by the same number each time.
Eg. 2, 4; & 16
vi #8 |e; or: 2% 9, 3 de
ol
X =P Xie X
wi
ol
Powered by (3 CamScannerener eral term (Tn) ji a
a stant dif ference ]
10, IS; Constant difference = +3
| 5 4 16;
| a Think of squares, cubes or other
exponents. How can you use these to write
| the original sequence? E.g.:
(i Te Ts Te Tn
lates 9) 16
You can write each term in the
r Bg Be ye pattern (I; 45 9% .) aS @ square,
Now find the connection between the number
he term and the sequence (V';2° 3°; 4:
Tigi
123
Powered by CamScannerAlgebraic expressions and Substitution NN
5 2 2x°
5x? + SEY + ~2Y 12+ yay |
Variable
Constant:
Coefficient:
Exponent:
aletter of the alphabet, &
xory
(x or y can be anything, Its
value can change.)
a number that stands by
itself, eg. 5 or ~12
(5 will always be 5. Its value
cannot change.)
the number (and its sign) which
you find in Front of a variable
(eg, -x?= (x?
»> the coefficient of x?
in -x? is -1)
The exponent of - x? is 2.
Powered by CamScannerYr
poor + SKY? +2 og. a+ yrs
Like terms:
Terms with the same type of variables,
eg. Sex? and 2 ( (there is an x? in both)
Remember: xy? = yr
ary? and yx are therefore like terms too.
The order of the letters does not matter.
Unlike terms:
Terms with different types of variables,
eg, Say? and = 2y
Remember: 2%07y, 3xy’, - 5% and 2x? are all
unlike terms +00.
Remember:
+ You can add or subtract like terms only. ”
* Terms are separated by a + oF =.
~
Powered by CamScannerFactorisation
« Factorise » write an expression as
something x some thing (eg. bracket x bracket)
+ You can check your answer: Multiply the
bracket(s) > you should get the Original tern
once again,
Type Example
/Common factor 2xy + 4x0?
| = 2xc(y + 2x0)
Difference of xc? - 25y" |
| squares (2 terms)
= (x - sy)(x + 5y)
Trinomial
(4 or 5 terms)
x? +5x-6
(3 terms) = (x +6) -1) |
a —¢
Grouping 2x + 2y-x2-xy
'
=an+y)-xlx+y) |
j
= (x + y(2-x) Z
a
Powered by CamScanner(a) Gommon factor
Always look for a common Factor first,
4axs +2xty
= 2x%(2x0 + y)
1, Look for the greatest number that can
divide into all terms: 2
2. Look for the letter(s) that appear in all
Lerms: x
Choose the smallest exponent of this
letter (because this power can divide into
all terms): x2
= common factor: 2x?
3. What, should you write in the bracket?
By what should you multiply 2x? to get
the original terms once again?
> 20%X2x + y)
or
go? 2ety)
(s+ Be 2a aE st
ial
Powered by CamScanner4 pif ference of squares (2 terms) 7
4x? -|
/ \
[|
yx? Vl
[|
= (2x - 1)(ax +1)
| Is there a common factor? No,
2, Number of terms: 2
| Ts this a difference (-) of squares?
Check:
a) Are both terms perfect squares? Yes.
b) Is there a minus (a difference)? Yes.
: Difference (-) of squares
» This becomes!2 brackets:
one with a - and one with a +
Write - and + in the brackets straight away.
Then fill in the rest. i
Powered by CamScannerPr +6 Standard form:
ay 5 exponent, x2 rm
(nt able +3) y Ne constant
, mitSE'+6 term
Js there @ common Factor? No.
t
"Number of terms: 3
. yas this a trinomial in standard Form
(2+! + number)? Yes.
5) Find the Factors:
» Write x's in left column (factors of x).
. Write factors of +6 in right column
(+6 = factors: same signs > both + or both -).
« Cross multiply and write answers below.
+ Add these janswers.
Which combination gives middle term (+52)?
= -2
y
x -3
fae -3x
Powered by CamScanner|
nN
&
oa
ping (q or 5 terms) :
ax - ay +2n-2y \
= aay) + 2224)
=(x-y)la+2)
_ Is there a common factor?
No, not in all terms.
, Number of terms: 4
Is there a common factor in 2 of the terms?
Group. Form 2 groups so that you can take
out a common Factor from each group.
a) ax -ay = common factor: a
b) jae 2y = common factor: 2
- Take out common factor from each group:
= a(x -y) + lx -y)
. Now take out the new common Factor (x y)
= alse = y) + lary) ——
Everything that is left
= (a= ya 2) goes into this bracket.
Powered by (3 CamScannerFactorisation ee
320y - lay .
= Syl? 4)
= 3y(x - 2)(x +2)
| Is there a common factor? Yes,
= common factor: 34
1, Look at the bracket (x*-4).
Can you factorise this further?
3, Number of terms in bracket: 2
« both terms in bracket ore perfect, squares
« minus (- )
«. This is a difference of squares.
+ syle? 4) = syle 2)ee +2)
Powered by (9 CamScannerAlgebraic fractions
2-4 KP +2e-3 Ww
—_—a —_—_ Tr
jerg ax-ma 3
« first step: factorise
(common factor, difference of Sum
trinomial, grouping)
+ see what can cancel out
then simplify
X-1. 6-2K
[ez th
3
+ make denominators the same (LCM)
. then simplify
178
Powered by (9 CamScannert
|
|
Equations with x:
5X-6+X=10-2x0
sn-6 +x =10-20
srtxt2e =l0+6
gx =16
x =2
Equations with x2:
|. x's to one side
2. Numbers to other
side
x?-3x=4
x?-3x =4 I.
x2-3x-4 =° .
(x-4)la+i) =°
x-4=0 or xt+l=0
x=4 or xe -l
Everything to one side
(get 0 on the other side)
Factorise
Remember:
o x anything = 0
«either (x - 4) must be 0
= (o)(x+)=0
or (xc +1) must be 0
> (x-4)lo)=0
Powered by (9 CamScanneraphs (straight lines)
Gr
Gon of a straight line
y =mx+c Standard form
How steep the line is
(the inclination)
- gradient
‘ey-inbercept Where the line cuts
(intersects) the y-axis
vt J, NB! yis always on top
This is the same as:
Ax change in x
You need 2 points on a graph to
work out the gradient (m). vot
Powered by CamScannerie Description
‘Gradient, (m) | Sketch
mis 8 + Line lopes: Up (deg)
' : From left {0 right
“m>o * « If L walk on the
(positive) ‘ graph from left to
.
d
eg yea nig, wo
Ae nctencest . Graph is iscend
y increases too. (increasing).
mis — « Line slopes down (Fall)
from right,
emo + If Twolk on the |
(negative) graph From et to |
eg. y= - x4! right, I wolk downhill |”
« Graph is descending
If x increases,
| y decreases. (decreasing).
“
m=0 +—+— + Line runs horizontally,
/ mis |
|
a
24
Powered by CamScannerdycintercept
_ To find the x-intercept:
> let y=0 and find x
| To find the y- intercept:
> let x=0 and find y
Horizontal lines
Equation: eg. oie -3
« Cuts y-axis
+ Parallel to x - axis
+ Gradient = 0
Tip: Lf a line intersects (cuts) the y-axis only
> then the equation contains a y only.
203
Powered by CamScannerEquation: og be?
+ Parallel to y-axis ;
. Gradient is undefined
Tip: If a line intersects (cuts) the x - axis op|
= then the equation contains an x only
Parallel (|
Fis parallel to g: . » £4
“Fil ke i
° m, =m, (=2)
204
Powered by [@ CamScanner, pendicular (1) lines
y
cis perpendicular to h:
tah
m, X m,= -I
|
|
a2x-9
£
. gradient, of F x gradient of h = -1
Collinear points
. A,B and C are collinear,
+ This means you can
draw a straight line
through all 3 points. A
* Mag = Mac = Mac
+ The gradients of AB, BC and AC are all the
same,
A, Band C all lie on the same straight line.
(‘cot = together; "linear" = on a line)
Powered by CamScannergeomet oO
gles and lines
f straight lines
| Tria
co Statement Redan
A=B=C=6o" | (AARC is equilateral)
Cc
B an
A B=C (Zs Opposite equal sides)
OR:
- (equal sides; equal zs)
8
A AB=AC {sides opposite equal zs
OR:
, c (equal 2s, equal sides)
J~\ A+B+C=1g0° | (interior Zs of A)
8 c
A
C,=A+B (exterior £ of A)
you also have +0 say which lines
are |I,
+ Alt. Zs and corresp. 2s are only = when the
lines are |I.
+ Co-int. Zs are only supplementary (= 180°) when
the lines are ||.
IMPORTANT:
|. First state what = what,
Write down an equation.
2. Then write down your reason,
How do you know these are =?
= There is often more than | method,
Your reason just needs to match
nag Whatever you are stating,
Powered by CamScannerf 2D objects
Gomer) ol
spties oF quadrilaterals
| gE re
slog” - « both pairs oF opp, sides =
| — © both pairs of Opp. sides ||
¢ both pairs of Opp. Ls =
° diagonals bisect each other
both pairs of Opp. sides 2
« both pairs of opp. sides ||
+ both pairs of Opp. Zs =
° diagonals bisect each other
“AND:
\s diagonals =
|e each interior 2 = 90°
Rhombus e both pairs of opp. sides =
e both pairs of opp. sides ll
¢ both pairs of opp. 2s =
° diagonals bisect each other
AND: |
e all 4 sides =
. diagonals intersect L |
. diagonals bisect ds |
Powered by (9 CamScanner
!
|Oquare
Trapezium
+ both pairs of “OPP. sid |
« both pairs of opp
+ both pairs of opp. 1,
. diagonals bisect each
AND:
. diagonals =
+ each interior £ = oe
AND:
e all 4 sides =
. diagonals intersect, |
diagonals bisec bisect zs
si te,
;
| pair of opp. sides les ||
. diagonals intersect L
* both pairs of adjacent
sides =
* | pair of opp. ds = |
+ longer diagonal bisects |
shorter diag onal
+ longer dogo bisects 48
Powered by CamScannerem OT ye
4cm
% is the hypotenuse:
A Re Vy y? (Pyth)
is0m x is not the hypobenuse
17? = x? 415? (Pyth)
47cm
x? =IF°-15? (Pyth)
Ina right - angled A:
(gest side)? = (short side)? + (other short side)!
In an obtuse - angled A:
longest side)? > (short side)? + (other short side)?
| In an acute - angled A:
Inst ide)? < (short side)? + (other short, side)
Remember: — of ten more than | me netho J.
Your reasons just need +o match your s statements
_—_——
Powered by CamScannerCongruence and similarity
« side, side, side
(SSS)
side, angle, side
(SAS or SZS)
+ angle, angle, side
(AAS or ZZS)
« 90°, hypotenuse, side
(ao"HS or RHS)
« angle, angle, angle
(AAA or zzz)
e sides in
proportion
ce
Powered by CononE
(g55)— «iB c
|
D
el The order of the letters is important.
A and F both lie opposite the iside with
jhash mark (BC and DE, which are equal).
|, . Aand F are corresponding Ls ("buddies")
as they lie opposite corresponding sides.
» Therefore you write A and F in the same
position in AABC= AFDE.
In the same way:
| 8 and B both lie opp. side with 2 hash marks.
(ond E both lie opp. side with 3 hash marks,
You could also write: ABAC=ADFE, for example.
Order of + A's letters doesn't matter, as long as
Corresponding letters are in corresponding positions
Powered by CamScannerene” 4 x side a
es we (= side x side)
E- Area = 5 x x diagonal x diagonal 2
Rage
“perimeter = 2 + 2b
=2(£+b) Ld
Areas & x b
Perimeter = side + side + side
Area = sbase x Lh
—
7S
Powered by (3 CamScannerCircumference = 27
Area = tr?
Tip: Both formulae have a 2 somewhere,
Deena eee
Circumference: 211r Area: tr?
SU EUUDGET AEDST UST SEPSUNE IV, SSS Ipemree ee
Measure perimeter in cm, Measure area in cm?
j
m, etc. (not squared) m?, ete.
Just rin formula (not |r? in Formula
squared)
© Pavallelogram
Perimeter = 24 + 2b
Area=base x Lh
Perimeter =all the sides
Area = tb) x ‘Lh
296
Powered by 9 CamScannerperimeter =4 x side
A /
—h
jyea= BASE X ih
_#——.
| fs
yy Area = 5 x diagonal x diagonal 2
Perimeter = (2 x short side) + (2 x long side)
fre = , x diagonal x diagonal 2
Kite with
4 equal sides
. rhombus
Square, rhombus and kite:
Area = 5 x diagonal | x diagonal 2
297
Powered by 9 CamScannerace area and volume
su
Rectangular prism
Surface areq
Surface
area =2 rectangles + 2 rectongles + 2 rectangles
= 2(€ x h) + alb x h) + (£ xb)
= 2(th) + albh) + 2(£b)
Volume
| Volume = area of base x h
=t{xbxh
= tbh
321
Powered by CamScannerCube (a special rectangular prism)
Surface area
=6 squares
2
=6 x side
side
Volume =area of base x h 4)
= side x side x side
= side"
side
322 4 i
, —
Powered by 9 CamScannerTriangular prism
pds + rectangle + rectangle + rec tangle
aeave
A;bxh) + + (€xb) + (xb) + (£xb)
'ealsbh) - th + th +. b
Volume = area of base x H
=area A xH
H
= tbxhxH
(hed height of A; H = height of prism)
323
Powered by 9 CamScannerCylinder
Surface area
Think of the label around a tin of
sweetcorn (tin = cylinder).
If you remove the label and lay it down flat, it
looks like this:
Label is a rectangle
when you remove it,
- TSA = circle on top + circle below + rectangle
(total surface area)
Area of rectangle = length x breadth
+ Length of rectangle = circumf, (2mn) of circle
(as the label Folds around the tin)
« Breadth of rectangle = height (h) of tin
a8 (cylinder)
—
Powered by CamScannerr
tA-O+O+[ ]
eur’ + tr? + “xb!
eur? + Tr? + 2tpxh |
= 2? +2Trh
Volume
Jolume = area of base x h
=r xh h
=arh
NB! When you calculate volume:
. Triangular prism > base is always a A
* Cylinder = base is always circle
Note: TSA = total surface area os
Powered by CamScanner« Shift up or down > y + Or -
eg, (2, - 3) shifts 2 up
2 y- coordinate + 2
= (2, -3+2) = (2-0)
Rule: (x; y) > (x; y+2)
Tf a point shifts 2 units down = Rule: x. y)>
© ShiFt right or left > x: + on -
eg. (2; -3) shifts 2 leFt
= x-coordinate - 2
> (2-2, -3) = (0; -3) |
Rule: (x; y) + (2-2, y) |
TF a point Shifts 2 units £0 the night |
= Rule: (x, y)>(ee2, y) |
Powered by (3 CamScannerProbability
Definitions:
PIA) probability
/ = the chance that A will happen
=> P(A)= a
| |= 0«< PIA) <
nA)
n(S)
Outcome
“something newer happen
‘the mie of times something
\(event A) can happen
(the paper of outcomes)
sample space
> all possible outcomes
(everything that could possibly
_| happen)
the total umber ee ee in
the sample space
| Randomly
bina (without | looking)
Powered by CamScanner