Question

F (x)=8- 4x – x^3g(x) = x2 + 7x - 9Find f (x) + g (x)

Answer 1

In order to sum two polynomials, we can group the powers with the same exponent:

f(x) + g(x) = 8 - 4x - x³ + x² + 7x - 9

= (8 - 9) + (-4x + 7x) - x³ +x²

= -1 + (7 - 4)x - x³ + x²

= -1 +3x - x³ + x²

= -x³ + x² + 3x - 1

Notice that, in the last step, we just wrote the result in the standad form beginning with the power with larger exponent, then the next larger, and so on.