Question

Find (f - g)(x)

f(x) = 3x2 – 2x
g(x) = 9x2 - X+7

A. -6x2 - x-7
B. 6x2 – x+7
C. 12x2 - x-7
D. -6x2 – 3x-7

Answer 1

Explanation:

3x^2 - 2x - 9x^2 + x - 7

-6x^2 - x - 7

answer is A

Answer 2

A

Explanation:

We have the two functions:

`f(x)=3x^2-2x\text{ and } g(x)=9x^2-x+7\\`

And we want to find:

`(f-g)(x)`

This is equivalent to:

`=f(x)-g(x)`

Hence, by substitution:

`=(3x^2-2x)-(9x^2-x+7)`

Distribute:

`=(3x^2-2x)+(-9x^2+x-7)`

Rearrange:

`=(3x^2-9x^2)+(-2x+x)+(-7)`

Combine like terms:

`=-6x^2-x-7`

Hence, our answer is A.