|x+3|+（x+2y）^2=0,求（3分之2x）^2+（-4）（-2xy+3y^2）的值

2x²-3xy=y²=0（x,y不得o）求x/y+y/x 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知x-3y=0,求(2x+y)/(x^2-2xy+y^2)X(x-y) 已知2x-y=0,求分式【1+（3*y*y*y/x*x*x-y*y*y）】/【1+（2y/x-y）】的值注：x*x*x-y*y*y=（x-y）*（x*x+xy+y*y） 已知（x+2）^2+|x+y+5|=0,求3x^2y-[2x^2y-(2xy-x^2y)-4x^2]-xy 已知：（x+2)²+|x+y-2|=0,求3x²y+{-2x²y-[-2xy+(x²y-4x²）]-xy} | x |=3,x+y=0,且x-y大于0,求| x+2 |-（y-3）的平方 2．已知/x+3/+/y-x+4/=0 求（x-y）（x+y）的值 求导数y=3x-x^2 求y',y'/ x=1 y'/x=0 已知实数x、y满足|2x-y+1|+3根号3x-2y+4=0,求代数式[(x-y)/(x-2y)]/(x的平方-2y)/[(x的平方-y的平方）/x的已知实数x、y满足|2x-y+1|+3根号3x-2y+4=0,求代数式[(x-y)/(x-2y)]/(x的平方-2y)/[(x的平方-y的平方）/（x的 |3x-2|（x+y）²=0求x和y 已知（x+y）2 =2,(x-y)3 =3,求(x+y)7(x-y)2(x+y)3(y-x)4 的值 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 已知|x|=2,|y|=3,|x+y|=-(x+y)求x-y x+y分之x-y=-2,求3（x+y)分之x-y减去x-y分之2（x+y）的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² y=3(x-y),x=2(x-y)求x,y的值