y/1*2+y/2*3+y/3*4+……+y/2008*2009=2008 求y,分有的是,y/1*2+y/2*3+y/3*4+……+y/2008*2009=2008五分钟之内给出答案,还有送分

y (3y^2+8y-3)-6y(3y+2y-1)+9y 4y²-4y/y²-2y+1÷(y+1/y-1-y-1/y+1)÷(3y+3) (y-4)(3y+2)-(3y-7)(2y+1),其中y=4/3 2(y-4)(3y+2)-5(-3y+7)(y+1),其中y=-1 解分式方程（y+3)/(y^2+y)-1/(1-y)=4/y要过程 (3y+2)(y-4)-3(y-2)(y-3) (y^2)^4y-(-2y)^3y^6= 通分 y+3/y*y-6y+9,1/2y+6,y-1/y*y-9 数学题=y(y+3)-4(y+3)2=(y+3)(y-4y-12) y(y-2)²-y(y+3)(y-5) y=1/2 化简求值 y(y-2)²-y(y+3)(y-5) y=1/2 化简求值 y(y-2)²-y(y+3)(y-5) y=1/2 化简求值 (4-y)^2-4(1-y)(3+6y) 4y的平方-3y-1=y-2 y-1/y-2 - y-3/y-4=y-2/y-3 - y-4/y-5一共有四个分数哦~希望可以快一点~谢谢! 计算：[(y+1)/(y^2-4y+3)减去(y-2)/(y^2-6y+9)]除以(y-5)/(y-1) 常微分方程的通解dy/dx=(x-y+1)/(x+y-3)y^4=2y^n+y=0y''+6y'+9y=e^(-3x)y''+y'-2y=4e^(2x) 化简(x+y)-(2x+y/2)-(3x+y/6)-(4x+y/12)-(5x+y/20)-……-(10x+y/90)