求(x-2y)²-4(2x-y)²=?16(x+y)²-25(x-y)²=?a的
求(x-2y)²-4(2x-y)²=?16(x+y)²-25(x-y)²=?a的
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
若|x+y-1|+(x-y-2)²=0,求代数式(x+2y)(x-2y)-(2x-y)(-y-2x)的值.
已知2x-y=10,求代数式[(x²+y²)-(x-y)²+2y(x-y)]÷4y的值?
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
求因式分解(x-y)²-2(x-y)³和(x+y)(x-y)-x(x-y)
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
(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
4/X+1/Y=2,XY=-1,求代数式4Y-X/X-2Y/(x+2y-12Y²/x-2y)的值
已知x²-y²=10,求[(x+y)³-2y(x+y)²-4(x+y)]÷(x+