1、2bx—ax—10by+5ay2、（x^2-y+1)(x^2+1)+x^2y+y-x^23、(x+5y)^2+(2x+10y)(3x-y)+(y-3x)^2

Question

1、2bx—ax—10by+5ay
2、（x^2-y+1)(x^2+1)+x^2y+y-x^2
3、(x+5y)^2+(2x+10y)(3x-y)+(y-3x)^2

Answer 1

1.2bx-ax-10by+5ay=x(2b-a)-5y(2b-a)=(x-5y)(2b-a)
2.（x^2-y+1)(x^2+1)+x^2y+y-x^2=（x^2-y+1)(x^2+1)+x^2y+y-(x^2+1)+1
=(x^2+1)（x^2-y+1-1)+y(x^2+1)+1=(x^2+1)x^2+1=x^4+2x^2+1=(x^2+1)^2
3.(x+5y)^2+(2x+10y)(3x-y)+(y-3x)^2=(x+5y)^2-2(x+5y)(y-3x)+(y-3x)^2
=(x+5y-y+3x)^2=(4x+4y)^2=16(x+y)^2