Q15 of 99 Page 53

Let f : R → R : f(x) = 3x + 2, find f{f(x)}.

To find: f{f(x)}


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


Given: (i) f : R → R : f(x) = 3x + 2


We have,


f{f(x)} = f(f(x)) = f(3x + 2)


f o f =3(3x + 2) + 2


= 9x + 6 + 2


= 9x + 8


Ans) f{f(x)} = 9x + 8


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