Given f(x) = 2x2 − 3 and g(x) = x + 8, identify g(f(4)).

Answer 1

We can work this from the inside out.

First, f(4) = 2(4²) - 3 = 2(16) - 3 = 32 - 3 = 29

So, g(f(4)) = g(29) = 29 + 8 = 37

Answer 2

I'm assuming that f(x) is really supposed to be 2x²-3. In that case, to find g(f(x)), you just plug in f(x) in place of x for g(x), so that would look like...

g(f(x)) = (2x²-3) + 8 = 2x²+5

So when you plug 4 into this equation, you get...

2(4)² + 5

= 2(16) + 5

= 32 + 5

= 37

Therefore, g(f(4)) = 37

Answer 3

If f(x)=2x^2-3 and g(x)=x+8, to find g(f(4)) we need to use the rules for compositions of functions.

Start from the inside and work your way out.

what is g(4)? plug 4 into the x in the g(x) function, g(4)=4+8=12

now plug 12 into the f(x) function.

you should get 285