(1) 2x²+2x-1
=2(x²+x-1/2)
=2(x²+x+1/4-3/4)
=2[(x+1/2)²-3/4]
=2(x+1/2+√3/2)(x+1/2-√3/2)
(2)x²-2xy-y²
=(x²-2xy+y²)-2y²
=(x-y)²-2y²
=(x-y+√2y)(x-y-√2y)在实数范围内是的,两个都是在实数范围内分解的,在有整数范围内是不能分解的还问一个问题行吗?行,问吧,只要等一会采纳就行a²-b²-2b-1=a²-(b²+2b+1)=a²-(b+1)²=(a+b+1)(a-b-1) 请采纳