Question

Given f(x)=x^2+3 and g(x)=x+5/x. Find (g o f)(4)

Answer 1

To find g(f(4)), work from the inside out.

f(4) is 4^2+3, or 16+3, or 19.  Now, we must find g(19).

This is 19+5/19.  This is already a mixed number, though if you want an improper fraction solution, we have:

361/19+5/19

Which simplifies to:

366/19

Therefore, 366/19 is the answer.