Answer:
A. 3x²+1
Step-by-step 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
