求解微分方程dy/((y^2-1)^(1/2))=dx
问题描述:
求解微分方程dy/((y^2-1)^(1/2))=dx
答
令y=1/cost,dy/((y^2-1)^(1/2))=dt/cost=dsint/(1-(sint)^2)
令u=sint,dsint/(1-(sint)^2)=((1/(1+u)+1/(1-u))/2)du
两边积分得(ln(1+u)-ln(1-u))/2=x+c
将u=sint,y=1/cost,带回,有-ln(1-u)=ln(1+u),
故积分式可化为ln(1+u)=ln|y+(y^2-1)^(1/2)|=x+c
答
能不能把问题写好一点啊
答
dy/((y^2-1)^(1/2))=dx
两边积分得:
ln|y+(y^2-1)^(1/2)|=x+C