几道因式分解的题求速答169x²-4y²=-(x+y)²+y²=-a²+ab-1/4b²=(x+1)(x+2)+1/4=

问题描述:

几道因式分解的题求速答
169x²-4y²=
-(x+y)²+y²=
-a²+ab-1/4b²=
(x+1)(x+2)+1/4=

169x²-4y²=(13x+2y)(13x-2y);-(x+y)²+y²=(y+x+y)(y-x-y)=-x(x+2y);-a²+ab-1/4b²=-(a²-ab+b²/4)=-(a-b/2)²;(x+1)(x+2)+1/4=x²+3x+2+1/4;=x²+3x+9/4;=(x...