Question

please answer the question on the screenshot below, also please explain to me how you got your answer.

Answer 1

QUESTION 1

The given functions are;

$f(x)=5x^2-2x$ and $g(x)=5x^2+x-4$

$(f+g)(x)=f(x)+g(x)$

$(f+g)(x)=5x^2-2x+3x^2+x-4$

We regroup like terms to obtain;

$(f+g)(x)=5x^2+3x^2-2x+x-4$

This simplifies to;

$(f+g)(x)=8x^2-x-4$

The correct answer is A.

QUESTION 2

The given functions are;

$f(x)=3x^2+5$ and $g(x)=x-2$.

$(fg)(x)=(f(x))(g(x))$

This implies that;

$(fg)(x)=(3x^2+5)(x-2)$

$\Rightarrow (fg)(x)=3x^3-6x^2+5x-10$

The correct answer is B.

QUESTION 3

The given functions are

$f(x)=3x^2+10x-8$ and $g(x)=3x^2-2x$.

$(\frac{f}{g})(x)=\frac{f(x)}{g(x)}$

$(\frac{f}{g})(x)=\frac{3x^2+10x-8}{3x^2-2x},x\ne0,\frac{2}{3}$

We factor to obtain;

$(\frac{f}{g})(x)=\frac{(x+4)(3x-2)}{x(3x-2)},x\ne0,\frac{2}{3}$

We cancel the common factors to obtain;

$(\frac{f}{g})(x)=\frac{x+4}{x},x\ne0,\frac{2}{3}$

The correct answer is A.