求解两道高数题:求微分方程的通解:1,(y^2-6x)dy+2ydx=0. 2, (x-y^3)dy+ydx=0(y>0) .求解答,不胜感激!

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求解两道高数题:求微分方程的通解:1,(y^2-6x)dy+2ydx=0. 2, (x-y^3)dy+ydx=0(y>0) .求解答,不胜感激!

求解两道高数题:求微分方程的通解:1,(y^2-6x)dy+2ydx=0. 2, (x-y^3)dy+ydx=0(y>0) .求解答,不胜感激!
求解两道高数题:求微分方程的通解:1,(y^2-6x)dy+2ydx=0. 2, (x-y^3)dy+ydx=0(y>0) .求解答,不胜感激!

求解两道高数题:求微分方程的通解:1,(y^2-6x)dy+2ydx=0. 2, (x-y^3)dy+ydx=0(y>0) .求解答,不胜感激!
构造全微分方程.

  1. (y^2-6x)dy+2ydx=0,   dx/dy-3x/y=-y/2,  是x对y的一阶线性微分方程,则

     x = e^(∫3dy/y)[∫(-y/2)e^(-∫3dy/y)dy+C]

      = y^3[-∫dy/(2y^2)+C] =  y^3[1/(2y)+C] = y^2/2+Cy^3...

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    1. (y^2-6x)dy+2ydx=0,   dx/dy-3x/y=-y/2,  是x对y的一阶线性微分方程,则

       x = e^(∫3dy/y)[∫(-y/2)e^(-∫3dy/y)dy+C]

        = y^3[-∫dy/(2y^2)+C] =  y^3[1/(2y)+C] = y^2/2+Cy^3.

    2. (x-y^3)dy+ydx=0  (y>0),  dx/dy+x/y=y^2,  是x对y的一阶线性微分方程,则

      x = e^(-∫dy/y)[∫y^2*e^(∫dy/y)dy+C]

        = (1/y)[∫y^3dy+C] = (1/y)[y^4/4+C] = y^3/4+C/y.

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