Given that f(x)=8x+5 and g(x)=4x^2+5x then do the following?

Question

(FoG)(1)=


(FoG)(x)=

Answer 1

(F o G)(anything) = f(g(anything))

For (FoG)(1) = F(G(1)),

1. First evaluate G(1). You will get a value for G(1).
2. Evaluate F(G(1)), replacing G(1) with the value you found in step 1.

Similar steps will solve (F o G)(x).

Answer 2

Remember (f ○ g)(x) = f(g(x)). So to find (f ○ g)(1), find the value of g(1), and plug that into f(x). Note that (f ○ g)(x) is not necessarily the same thing as (g ○ f)(x), which some people have calculated.

g(1) = 4 + 5 = 9
f(9) = 72 + 5 = 77

To find (f ○ g)(x), just take the whole expression of g(x) and plug it into f(x):

8(4x^2 + 5x) + 5 = 32x^2 + 40x + 5

Answer 3

(FoG)(x)= 8(4x^2+5x)^2+5(4x^2+5x)
so (FoG)(1)=8(4+5)^2+5(4+5)=8*81+45=693

Answer 4

For the first problem:
Put 1 into f(x) for x
f(1)=8(1)+5
f(1)=13 Put this into g(x) for x
g(13)=4(13)^2+5(13)
g(13)=741

For the second problem put g(x) into f(x)
f(g(x))=8(4x^2+5x)+5
f(g(x))=32x^2+40x+5

Answer 5

What's a (FoG)?