What is the general solution of the differential equation? : (x - 4) y^4 dx - x^3 (y^2 - 3) dy =0 (x4)y4dxx3(y23)dy=0

1 Answer
Jul 9, 2017

1/y^3 -1/y = 2/x^2 -1/x+ c1y31y=2x21x+c

Explanation:

We have the following Differential Equation in differential form

(x - 4) y^4 dx - x^3 (y^2 - 3) dy =0 (x4)y4dxx3(y23)dy=0

Which we can re-arrange as follows:

(y^2 - 3)/y^4 dy/dx = (x - 4)/x^3 y23y4dydx=x4x3

This is now a separable DIfferential Equation, and so "separating the variables" gives us:

int \ (y^2 - 3)/y^4 \ dy = int \ (x - 4)/x^3 \ dx

This is now a trivial integration problem, thus:

int \ 1/y^2 - 3/y^4 \ dy = int \ 1/x^2 - 4/x^3 \ dx

:. -1/y + 1/y^3 = -1/x + 2/x^2 + c

Hence the solution is:

1/y^3 -1/y = 2/x^2 -1/x+ c