分解因式 ⑴2x^2-2x-1 ⑵2x^3-7x^2+2x+3

分类: 作业答案 • 2021-12-31 11:57:47

问题描述：

答

⑴2x^2-2x-1
=2[x-(1-√3)/2][x-(1+√3)/2]
⑵2x^3-7x^2+2x+3
=2x³-2x²-5x²+5x-3x+3
=2x²(x-1)-5x(x-1)-3(x-1)
=(x-1)(2x²-5x-3)
=(x-1)(x-3)(2x+1)