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Question
Find fog and gof if : f (x) = x+1, g(x) = `e^x`
.
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Solution
f (x) = x+1, g(x) = ex
f : R→R ; g : R → [ 1, ∞)
Computing fog :
Clearly, range of g is a subset of domain of f.
⇒ fog : R→R
(fog) (x) = f (g (x))
= f (ex)
= ex+1
Computing gof:
Clearly, range of f is a subset of domain of g.
⇒ fog : R→R
(gof) (x) = g (f (x))
= g (x+1)
= ex+1
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