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Question
Find gof and fog when f : R → R and g : R → R is defined by f(x) = x and g(x) = |x| .
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Solution
Given, f : R → R and g : R → R
So, gof : R → R and fog : R → R
f(x) = x and g(x) = |x|
(gof) (x)
= g (f (x))
= g (x)
= |x|
fog) (x)
= f (g (x))
= f ( |x| )
= |x|
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