4xy+1-4x²-y²8x³+4x²-2x-1

4xy+1-4x²-y²8x³+4x²-2x-1
4xy+1-4x²-y²
8x³+4x²-2x-1

4xy+1-4x²-y²8x³+4x²-2x-1
4xy+1-4x²-y²
=1 - (4x²+y²-4xy)
= 1 ² - (2x-y)²
=(1+2x-y)(1-2x+y)
8x³+4x²-2x-1
=(8x³+4x²)- (2x+1)
=4x²(2x+1) - (2x+1)
= (4x²-1)(2x+1)
=(2x+1)² (2x-1)

第一题将4xy与后两项合在一起，得到=1-（4X2-4xy+y2)=1-(2x-y)2=(1+2x-y)(1-2x+y)
第二题将前两项和后两项分别合在一起，得到=（8x3+4x2)-(2x+1)=4x2(2x+1)-(2x+1)=(4x2-1)(2x+1)=(2x-1)(2x+1)(2x+1)=(2x-1)(2x+1)2

　　4xy+1-4x²-y²
=1 - (4x²+y²-4xy)
= 1 ² - (2x-y)²
=(1+2x-y)(1-2x+y)
8x³+4x²-2x-1
=(8x³+4x²)- 2x-1
=4x²(2x+1) - (2x+1)
= (4x²-1)(2x+1)
=(2x+1)(2x+1)(2x-1)
=(2x+1)²(2x-1)
记得采纳！