Question

分解因式：(x的平方-1)(9x的平方-6x-8)-63

Answer 1

(x^2-1)(9x^2-6x-8)-63=(x^2-1)(9x^2-6x+1-9)-63=(x^2-1)(9x^2-6x+1)-9(x^2-1)-63

晚上再想下