Question

Find f − g and its domain.

f (x) = 2x^3 − 5x; g(x) = x^2 + 8x +15

Answer 1

(f - g)(x) = 2x^3 - x^2 - 13x - 15

Answer 2

domain = (-inf, inf) because there are no restrictions (like negative square roots or possible division by zero)

Answer 3

oh good that's what I had thank you

Answer 4

why wouldn't you make the 2x^3 negative?

Answer 5

because it's f - g

(2x^3 - 5x) - (x^2 + 8x +15)

Answer 6

ohhhh! got it thank you!