计算:1.(x-2y)(1+x+2y+4y^2+2xy+x^2)2.若|a|=3,|b|=5,求|a+b|的值 3.-2^2+(-2)^2-(-1)^3X(1/3-1/2)÷1/6- | -2 |
问题描述:
计算:1.(x-2y)(1+x+2y+4y^2+2xy+x^2)
2.若|a|=3,|b|=5,求|a+b|的值 3.-2^2+(-2)^2-(-1)^3X(1/3-1/2)÷1/6- | -2 |
答
1.(x-2y)(1+x+2y+4y^2+2xy+x^2)
=x+x^2+2xy+4xy^2+2x^2*y+x^3 -2y-2xy-8y^3-4xy^2-2x^2*y
=x+x^2+x^3 -2y -8y^3
2.|a+b| = 8 or 2,or -2,-8
3.-1-2 = 3