Question

Please Help !!! If F(x)=5x^3 and g(x)=x+1, find (f • g)(x)

A. 6x^3
B. 5x^4+5x^3
C. 5x^3+1
D. 5x^4+1

Answer 1

(f * g)(x)=(5x^3)*(x+1)=5x^4 +5x^3

Answer 2

B.
`5x^4+5x^3`

Explanation:

Given,

`f(x) = 5x^3`

`g(x) = x + 1`

We know that,

`(f\cdot g)(x) = f(x).g(x)`

`\implies (f\cdot g)(x) = 5x^3(x+1)`

`=5x^3.x + 5x^3.1` ( Distribution property of multiplication )

`=5x^(3+1)+5x^3` ( Product of powers property )

`=5x^4+5x^3`

Hence, option B is correct.