2(y+2)-3(4y-1)=9(1-y)应该怎么做啊每一步都要写为什么.好了后我加分.决不食言

y (3y^2+8y-3)-6y(3y+2y-1)+9y 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) (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 通分 y+3/y*y-6y+9,1/2y+6,y-1/y*y-9 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 [T,Y]=ode45(@rigid,[0 1],[rand(15,1)]);plot(T,Y(:,1),'-',T,Y(:,2),'-.',T,Y(:,3),'.',T,Y(:,4),'-',T,Y(:,5),'-.',T,Y(:,6),'.',T,Y(:,7),'-',T,Y(:,8),'-.',T,Y(:,9),'.',T,Y(:,10),'-',T,Y(:,11),'-.',T,Y(:,12),'-.',T,Y(:,13),'.',T,Y(:,14),'-',T,Y(:,15),'.') y- 2y+1/2=9- 8-y/4 y-2y+1/2=9-8-y/4 4y的平方-3y-1=y-2 Y的平方+3Y-1=0 y+3-1/y=0 y-1/y=-3 (y-1/y)^2=9 y^2+1/y^2-2=9 y^2+1/y^2=11 (y^2+1/y^2)=121 y^4+1/y^4+y^2+1/y^2-2=9y^2+1/y^2=11那个-2是怎么来的? 计算：[(y+1)/(y^2-4y+3)减去(y-2)/(y^2-6y+9)]除以(y-5)/(y-1) 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! (y-2)(y^2-6y-9)-y(y^2-2y-15),其中y=1/2.先化简再求值. 方程y''-4y'+13y=0的通解方程y''=(1+y'*y')/2y的通解