√X/Y+Y/X+2-√X/Y-√Y/X(注√X/Y+Y/X+2在一个根号2中)

先化简 再求值 (2x-y)(y+x)-(x-2y)(2y+x)-(-3y+x)^2其(√x+1)+y^2+4=-4y x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 {(x,y) |x|+|y| x>y?x:y 计算：｛x√x+x√y / xy-y²}-{x+√xy+y / x√x-y√y} 化简y(x+y)+(x+y)(x-y)-x^2 √X/Y+Y/X+2-√X/Y-√Y/X(注√X/Y+Y/X+2在一个根号2中) 计算：（x√y/x-2y√x/y)(x√y/x+2y√x/y)求你们帮帮忙啊 (x+y)(x-y)-(x-y)^2如题 (x+y)(x-y)-(x-y)^2 【2(x-y)(x-y)(x-y)-8(x-y)(x-y)(x+y)+6y(x-y)(x-y)]/2(x-y)(x-y) 因式分解x(x+y)(x-y)-x(x+y)^2 若x>0,y>0,且√x(√x+√y)=3√y(√x+5√y),求2x+2√x*√y+3y/x-√x*√y+y y^2-2(√x+1/√x)y+3 y=arcsin(x/√1+x^2),求y' y=ln(x+√x^2+1),求y RT,若（√2x-y）+y^2+4y+4=0,求[(x-y)^2+(x+y)(x-y)]÷2x的值 求一阶微分方程y'=(y√y)/(2x√y-x^2)的通解 y=2x+√(1-x)