Question

find (
–
10x2+x–9)–(
–
9x2–1)

Answer 1

Compute term-by-term:

(−10x^2 + x − 9) − (−9x^2 − 1)
= −10x^2 + x − 9 + 9x^2 + 1
= (−10x^2 + 9x^2) + x + (−9 + 1)
= −x^2 + x − 8.

So the result is −x^2 + x − 8.