题目

1.a^2-a^2b+ab^2-a+b-b^2 2.（x^2+x)(x^2+x-1)-2因式分解

提问时间：2020-11-22

答案

a² - a²b + ab² - a + b - b²
= (a² - b²) - (a²b - ab²) - (a - b)
= (a + b)(a - b) - ab(a - b) - (a - b)
= (a - b)(a + b - ab - 1)
(x² + x)(x² + x -1) - 2
= (x² + x)² - (x² + x) - 2
= (x² + x + 1)(x² + x - 2)
= (x² + x + 1)(x - 1)(x + 2)