Question

I am very confused. Please help! It says to find the indicated values. Given f(x)= 2x²+5x and g(x)= 3x
find f(g(x)).

Answer 1

$f(g(x))=2\cdot(3x)^2+5\cdot3x=18x^2+15x$

Answer 2

Note that f(x) = 2x² + 5x, and g(x) = 3x

Plug in 3x for x in f(x)

f(g(x)) = 2(3x)² + 5(3x)

Simplify. First square 3x

3x(3x) = 9x²

f(g(x)) = 2(9x²) + 5(3x)

Simplify. Multiply 2 with 9x², and 5 with 3x

2(9x²) = 18x² 5(3x) = 15x

f(g(x) = 18x² + 15x

f(g(x) = 18x² + 15x is your answer

hope this helps