计算:(1)y/4x²y-1/12y²;(2)2/x+y-x+3/x+y(3)a²/a+3
已知x-y=1,y≠0,求{(x+2y)²+(2x+y)(x+4y)-3(x+y)(x-y)}÷y的值.
计算:(1)2/(x+y)+4y/x²-y²(2)x²/x+y-x+y
计算(1)x/x+y-x/x-y (2)a+2+4/a+2 (3)x^2-y^2/xy÷(x+y)
计算:(a-b)(x-y)-(b-a)(x+y) 4+12(x-y)+9(x-y)²
x(x-y)-y(y-x)+(x-y)²因式分解
计算:(4y分之3x²)² × 3x分之2y + 2y²分之x² ÷ x分之2y
12x²-3y² (2x+y)²-(x+2y)²
先化简再求值:(x-2y)²-(x+2y)(x-2y)-(x-3y)(x-y).其中x²+9y
因式分解x²(x-2y)+y²(2y-x)
3y/2x+2y+2xy/x²+xy 2x/x²-64y²-1/x-8y (1/a+1/b
(1)计算:a-(a^2)/(a+1)-1 (2)计算:3x/(x-4y)+(x+y)/(4y-x)-7y/(x-4y)
计算 x+2y+﹙4y²/x-2y﹚+﹙4x²y/4y²-x²)