Cambridge Assessment International Education

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16
9
The function f is defined by f
x
=
2
−
3 cos
x
for 0
≤
x
≤
2
0
.
(i)
State the range of f.
[2]
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(ii)
Sketch the graph of
y
=
f
x
.
[2]
© UCLES 2019
9709/11/M/J/19

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17
The function g is defined by g
x
=
2
−
3 cos
x
for 0
≤
x
≤
p
, where
p
is a constant.
(iii)
State the largest value of
p
for which g has an inverse.
[1]
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(iv)
For this value of
p
, find an expression for g
−
1
x
.
[2]
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© UCLES 2019
9709/11/M/J/19