Question

f(x) = x +4g(x) = 3x2 – 7Find (f .g)(x).A. (f-9)(x) = 3.73 – 28O B. (f.g)(x) = 3x2 + 12x2 – 7x - 28OC. (f.g)(x) = 3.r3 +28O D. (f.g)(x) = 3.7° + 12.2 - 72 +28

Answer 1

Recall that:

`(f\cdot g)(x)=f(x)\cdot g(x)\text{.}`

Substituting f(x)=x+4 and g(x)=3x²-7 we get:

`\begin{gathered} (f\cdot g)(x)=_{}(x+4)(3x^2-7), \\ (f\cdot g)(x)=3x^3-7x+12x^2-28, \\ (f\cdot g)(x)=3x^3+12x^2-7x-28. \end{gathered}`

Answer: Option B.