Cambridge International Mathematics

ANSWERS 715

d

e

f

EXERCISE 21E.2

1a b

cd

ef

2a b

c

d

e

f

3ay=(x¡1)^2 +3

vertex is at(1,3)

by=(x¡2)^2 ¡ 1

vertex is at(2,¡1)

cy=(x+1)^2 +4

vertex is at(¡ 1 ,4)

dy=(x+2)^2 ¡ 3

vertex is at(¡ 2 ,¡3)

ey=(x+3)^2 ¡ 2

vertex is at(¡ 3 ,¡2)

fy=(x¡3)^2 +3

vertex is at(3,3)

EXERCISE 21E.3

1a iy=5x^2 is ‘thinner’

than y=x^2

ii graph opens upwards

x

y

(-2' -4)

(-1' 2)

(0' 4)

(1' 2)

(3'-14)

(2'-4)

(-3' -14)

y=- 2 xX+ 4

O

x

y

(-3' 10)

(-2' 6)

(-1' 4) (0' 4)

(1' 6)

(2' 10)

(3' 16)

y=xX+x+ 4

O

y x

(-3'-30)

(-2' -21)

(-1' -14)

(0' -9) (1' -6)

(2' -5)(3' -6)

y=-xX+ 4 x- 9

O

y

x

(3' 0)

@\=\!X

@\=\(!-3)X

O

y

x

(-1' 0)

@\=\!X

@\=\(!+1)X

O

y

x

(1' 0)

@\=\!X @\=\(!-1)X

O

y

x

(5' 0)

@\=\!X @\=\(!-5)X

O

y

x

(-5' 0)

@\=\(!+5)X @\=\!X

O

y

x

(Ew_' 0)

@\=\!X @\=\(!-\Ew_)X

O

y

x

(1' 3)

@\=\!X 4

O

y

x

3

(2'-1)

@\=\!X

O

y

x

(-2'-3)

1

@\=\!X

O

y

x

(-1' 4)

(^5) @\=!X
O
y
x
(-3'-2)
7
@\=!X
O
y
x
12
(3' 3)
@\=!X
O
x
y
@\=!X
@\=\5!X
O
x
y
(0' -1)
@\=!X
@\=!X-1
x O
y @\=!X
@\=!X-\3
(0' -3)
O
x
y
(0'-5)
@\=!X
@\=!X-5
O
x
y
(0' 1)
@\=!X
@\=!X+1
O
x
y
(0' 5)
@\=!X
@\=!X+5
O
x
y
(0' -\Qw)
@\=!X
@\=!X-\Qw
O
IB MYP_3 ANS
cyan magenta yellow black
(^05255075950525507595)
100 100
(^05255075950525507595)
100 100
Y:\HAESE\IGCSE01\IG01_an\715IB_IGC1_an.CDR Thursday, 20 November 2008 4:36:19 PM PETER