(x²+y²)(x²+y²+2)=3 求x²+y²的值!
若|x+y-1|+(x-y-2)²=0,求代数式(x+2y)(x-2y)-(2x-y)(-y-2x)的值.
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
已知方程组2x-y=10,x+2y=11,求(2x-y)³-(2x-y)²(x-3y)的值
已知x,y的值满足方程组x+2y=3,x-y=-2,求x/(x-y)²+x²-y²/(x+
已知2x-y=10,求代数式[(x²+y²)-(x-y)²+2y(x-y)]÷4y的值?
已知x-3y=0,y≠0,求x²-2xy+y²分之2x+y×(x-y)的值
已知方程组2x+y=6 x-3y=1,求7y(x-3y)²-2(3y-x)³的值
求因式分解(x-y)²-2(x-y)³和(x+y)(x-y)-x(x-y)
已知y-2x=0,求3x²-2y²/(x+y)(x-y)的值
已知x+3y=2,求代数式(x²-y²/x+y)-【2(x+y)】的值
当x=2,y=-1时,求代数式(x+y)(x-y)+(x-y)²-(x²-3xy)的值
已知|x+y+2|+(2x-3y-1)²=0 求 ⑴x、y的值 ⑵2x³-x²-3y