u=(x

u=(x u=(x 全集U=(x/x 集合U={x|x 设U={x|x 已知x/(y+z+u)=y/(z+u+x)=z/(u+x+y)=u/(x+y+z)求(x+y)/(z+u)+(y+z)/(x+u)+(z+u)/(x+y)+(u+x)/(y+z) 设全集U={X 全集U={x|o 设U={x|-5 请问 U|S=｛x, x(x+1)du/dx=u^2；u(1)=1 求u(x)=? du/dx=(x+u)^2求u的解 du/[u(u-1)]=dx/x详解 u=e的x次方,求u' 二阶线性微分方程 u‘’+2u=e^x du/(u-u^2)=dx/x怎么解, 设全集U ={x|x 已知全集U=﹛x|x