问几道因式分解的题目,把过程写出来.x²+2x-1 2x²+xy-y²-4x+5y-6x三次方-3x²+4
问题描述:
问几道因式分解的题目,把过程写出来.
x²+2x-1
2x²+xy-y²-4x+5y-6
x三次方-3x²+4
答
x²+2x-1 =x²+2x+1-2=(x+1)²-(√2)² =(x+1+√2)(x+1-√2)2x²+xy-y²-4x+5y-6=(2x-y)(x+y)-4x+5y-6=(2x-y)(x+y)+(2x+2y)-6x+3y-6=(2x-y)(x+y)+2(x+y)-6x+3y-6=(x+y)(2x-y+2)-3(2x-y+2)=(...