If f(x) = 1x + 2, what is f(f(1))?

We see that f(1) = 11 + 2 = 13. Therefore, f(f(1)) = f(13) = 113 + 2 = 173 = 37.

jmc

algebra intermediate

Problem

f (x) = \frac{1}{x + 2},

what is

f (f (1))

Solution

We see that

f (1) = \frac{1}{1 + 2} = \frac{1}{3} .

Therefore,

f (f (1)) = f (\frac{1}{3}) = \frac{1}{\frac{1}{3} + 2} = \frac{1}{\frac{7}{3}} = \frac{3}{7} .

Final answer

\dfrac{3}{7}