Question

If f(x) =3x2 and g(x)=4x3+1, what the degree of (f•g)(x)?

2
3
5
6

Answer 1

its D. 6

Explanation:

got it right on edge 2021

Answer 2

f(x) = 3x²

g(x) = 4x³ + 1

f(g(x)) = 3.(4x³ + 1)²

As we know

(a + b)² = a² + 2.a.b + b²

So,

(4x³ + 1) = (4x³)² + 2.4x³.1 + 1² =
`4x^6+8x^3+1`

f(g(x)) = 3.(
`4x^6+8x^3+1`)

The degree is the maximum exponent, so, 6.