Ответы и объяснения

2013-05-20T18:40:35+00:00

1) (3x+y)(2x-5y)-6(x-y)^2=6x^2-15xy+2xy-5y^2-6(x^2-2xy+y^2)=6x^2-15xy+2xy-5y^2-6x^2+12xy-6y^2=-x-5y^2-6x^2

2.(-2x^3y)^3*(-5x^2y)^2=-8x^9y^3*25x^4y^2=-200x^13y5

 

 

4) 1.ab+ac-a=a(b+c-1)

      2.4x^2+2x-y^2-y=2x(2x+1)-y(y+1)