Answer:
x^2 + 4x + 3
Explanation:
(f-g)(x) = (2x^2-5)-(x^2-4x-8)
Subtract x^2 from 2x^2 leaving us with x^2
Next, subtract -8 from -5 to get +3 (-5-(-8) = +3) this can also be written as (-5+8 = +3)
Lastly, the -4x turns into +4x as the subtraction will convert the negative into a positive (negative and a negative makes a positive)
We are left with: (f-g)(x) = x^2 + 4x + 3