求方程dy/dx=y/(x+y^3)的通解

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求方程dy/dx=y/(x+y^3)的通解求方程dy/dx=y/(x+y^3)的通解求方程dy/dx=y/(x+y^3)的通解dy/dx=y/(x+y^3)dx/dy=x/y+y²即dx/d

求方程dy/dx=y/(x+y^3)的通解
求方程dy/dx=y/(x+y^3)的通解

求方程dy/dx=y/(x+y^3)的通解
dy/dx=y/(x+y^3)
dx/dy=x/y+y²

dx/dy-1/y ·x=y²
所以
x=e^[-∫(-1/y)dy] (∫y²e^[∫(-1/y)dy]dy+c)
=y (∫y²/y dy+c)
=y(∫ydy+c)
=y(y²/2+c)
=cy+1/2 y³

(x+y^3)dy=ydx
xdy-ydx+y^3dy=0
(xdy-ydx)/y^2+ydy=0
d(-x/y)+(1/2)dy^2=0
d[(-x/y)+(1/2)y^2]=0
通解为:(-x/y)+(1/2)y^2=c