Let f : R → R : f(x) = |x|, prove that f o f = f. – InterviewSolution

InterviewSolution

1.

Let f : R → R : f(x) = |x|, prove that f o f = f.

Answer»

To prove: f o f = f

Formula used: f o f = f(f(x))

Given: (i) f : R → R : f(x) = |x|

Solution: We have,

f o f = f(f(x)) = f(|x|) =||x||= |x| = f(x)

Clearly f o f = f.

Hence Proved.

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