Question

If (f+g)(x) = 3x to the second power + 2x - 1 and g(x) = 2x - 2, what is f(x)?

O A 3x2+1
OB. 3x2-1
Oc. 3x2+4
OD. 3x2-4
O E. x2 -2

Answer 1

A. 3x²+1

Explanation:

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

given that

(f+g)(x)=3x²

g(x)=2x-2

f(x)=?

put in the values

3x²+2x-1=f(x)+2x-2

subtract 2x from both sides

3x²+2x-2x-1=f(x)+2x-2x-2

3x²-1=f(x)-2

add 2 on both sides

3x²-1+2=f(x)-2+2

f(x)=3x²+1