计算 (1/3x-1/2y)(1/2y-1/3x)
(2x+y)(x+3y-1)计算
计算3x[xy-2x(1/y-x/3]+3y(x²-y²)
计算:1/(x-y)-1/(x+y)-2y/(x^2+y^2)-4y^3/(x^4+y^4)-8x^7/(x^8+y^8
1.计算(a^2+a+1)(a^2-a+1) 2.计算(x-y)(x+y)+(3x-2y)(2x+y)-x(6x-y)
已知x=2+根号3,y=2-根号3,计算代数式(x+y/x-y-x-y/x+y)乘以(1/x^2-1/y^2)
计算:(2/3x√9x+6x√y/x)+(y√x/y-√1/x)
数学用乘法公式计算(x+y+1)(x+y-1)(2x-y-3)²
(1)计算:a-(a^2)/(a+1)-1 (2)计算:3x/(x-4y)+(x+y)/(4y-x)-7y/(x-4y)
计算(4x^2-2x^3+6x)/(-2x)-(x-1)^2y^2-4/y^2-y-6)+(y+2/y-3)/(y+1/
分解因式计算:x^2(x-y)+(y-x)=?x^3+x^2+1\4x=?(2x+y)^2-(x-2y)^2=?
(1)(2x-3y)的平方-(y+3x)(3x-y) (1~4是计算) (2)[(x-y)的平方+(x+y)的平方](x
计算:(x-y)(1/9x-y)-(1/3x-y)(1/3x+y)