微分方程y''-3/2y^2=0 满足初始y(0)=1,y'(0)=1

问题描述:

微分方程y''-3/2y^2=0 满足初始y(0)=1,y'(0)=1

设y'=p(y),则y''=dp/dx=dp/dy*p,原方程化为2pdp=3y^2dy,∴p^2=y^3+c,∴y'=土√(y^3+c),把初始条件代入得c=0,取正号,dy/√(y^3)=dx,-2/√y=x+c1,把初始条件代入得c1=-2,∴-2/√y=x-2,√y=2/(2-x),∴y=[2/(2-x)}^2,(x...