约分:xy(10x²-10xy)分之x²y(5y²-5x²)
计算:(xy-x²)乘 x-y分之xy
(xy-x²)除以xy分之x²-2xy+y²乘以x²分之x-y
(xy-x²)·x²分之x-y
约分(x²-y²)÷(3x²+6xy+3y²)
x-y/x²÷x²-2xy+y²/xy*(xy-x²)
约分:-20a²b分之5ab;x²-4分之x²-2x;x+y分之x³-xy
已知x²+y²-2x+4y+5=0,求(x²-xy)分之y减去(xy-x²)分之
约分:2x²y-2xy²/x²-2xy+y²
已知(x+3)+丨X-y+10丨=0 ,求5x²y-[2x²y-(3xy-xy²)-3x&
计算:(xy-x²)×x-y/xy
已知:x²+y²-4x-2y+5=0,求x+√xy分之(√x-√y)²+4√xy的值.
(xy-2y)÷(x²-4x+4)约分