Question

Let f(x)=x+5 and g(x)=x^2
find (g*f)(4)
9
81
20
1

Answer 1

If \(f(x) = x+5\) and \(g(x) = x^2\) then \((g*f)(x)) = (x+5)^2\), right? Evaluate that at \(x=4\) and you've got your answer.

Answer 2

So I would do (g*f)(4))=(4+5)^?

Answer 3

(4+5)^2

Answer 4

9^2=81

Answer 5

so is 81 my answer?

Answer 6

Yes, \[(g*f)(x) = g(f(x))\]
\[(x+5)^2 = (4+5)^2 = 9^2 = 81\]

Answer 7

Thank you so much!