Question

Let f(x)=x^2+7 and g(x)=x+3/x find (g°f)(-5)

Answer 1

Given that f(x)=x^2+7 and g(x)=x+3/x
then
(g°f)(x)
=(x^2+7)+3/(x^2+7)
hence:
(g°f)(-5)=[(-5)^2+7]+3/[(-5)^2+7]
=[25+7]+3/[25+7]
=32+3/32
=32 3/32

Answer 2

`\implies \bf(35)/(32)`

Explanation:

The function f(x) is given to be : f(x) = x² + 7

Also, The function g(x) is given to be :

`g(x) = (x+3)/(x)`

We need to find : (gof)(-5)

⇒ g(f(-5))

⇒ g((-5)² + 7)

⇒ g(32)

`\implies (35)/(32)`