QUADRATIC FUCNTIONS
2.13 The functions f and g are defined for real values of x by
f (x) =
x-1-3
for x 2 1,
g (x) =
x-2
2x - 3
for x 2 2.
(i) Find gf(37).
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(ii) Find an expression for f - 1 (x) .
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(iii) Find an expression for g -1 (x) .
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2.14
The functions f and g are defined for real values of x by
f ^xh =
2
+ 1 for x 2 1,
x
g ^xh = x 2 + 2 .
Find an expression for
f -1 ^xh,
(ii)
gf ^xh,
(iii)
fg ^xh.
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3x + 2
and solve ff ^xh = x .
x+2
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(iv) Show that ff ^xh =
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