1.若X+Y=0,XY=-6,则X³Y-XY³-52.计算:101²-99²= 3.(-2)²º¹²+(-2)²º¹¹= 4.分解因式:(a-b)²+4(a-b+1)

问题描述:

1.若X+Y=0,XY=-6,则X³Y-XY³-5
2.计算:101²-99²=
3.(-2)²º¹²+(-2)²º¹¹=
4.分解因式:(a-b)²+4(a-b+1)

X³Y-XY³-5
=xy(x^2-y^2)-5
=xy(x+y)(x-y)-5
=0-5
=-5
101^2-99^2
=(101-99)(101+99)
=2*200
=400
(-2)^2012+(-2)^2011
=2^2012-2^2011
=2*2^2011-2^2011
=(2-1)*2^2011
=2^2011
(a-b)^2+4(a-b+1)
=(a-b)^2+4(a-b)+4
=(a-b+2)^2