(1)
=(-8x^3y^6)(3x^3y^4/4)=-6x^6y^10
(2)
=(x-2y)^2-1-(x+2y)^2=[(x-2y)+(x+2y)][(x-2y)-(x+2y)]-1=(2x)(-4y)-1=-8xy-1
(3)=[(a^2-4)+3(a+2)+a+1]/(a^2-4)=(a^2+4a+3)/(a^2-4) a=0时,原式=-3/4
2.解不等式组:
(1)解不等式组 x-1<等于2
x-2<4x+4
x<等于3
-3x<6 x>-2
总之-2<x<等于3 其整数解有x=-1, 0 ,1, 2 ,3 .