Looking for answers? Westonci.ca is your go-to Q&A platform, offering quick, trustworthy responses from a community of experts. Discover solutions to your questions from experienced professionals across multiple fields on our comprehensive Q&A platform. Get detailed and accurate answers to your questions from a dedicated community of experts on our Q&A platform.

dy/dx=2xy/x²+y² solve​

Sagot :

Answer:

[tex]y=\frac{-1}{2} \sqrt[]{4x^2+4c_{1}^2} -c_{1}\ or \ \frac{1}{2} \sqrt[]{4x^2+4c_{1}^2} -c_{1}[/tex]

Step-by-step explanation:

As it is first order nonlinear ordinary differential equation

Let y(x) = x v(x)

2xy/(x²+y²)=2v/(v^2+1)

dy=xdv+vdx

dy/dx=d(dv/dx)+v

x(dv/dx)+v=(2v)/(v^2+1)

dv/dx=[(2v)/(v^2+1)-v]/x

[tex]\frac{dv}{dx}=\frac{-(v^2-1)v}{x(v^2+1)}[/tex]

[tex]\frac{v^2+1}{(v^2-1)v}dv=\frac{-1}{x}dx[/tex]

∫[tex]\frac{v^2+1}{(v^2-1)v}dv[/tex] = ∫[tex]\frac{-1}{x}dx[/tex]

u=v^2

du=2vdv

Left hand side:

∫[tex]\frac{v^2+1}{v(v^2-1)}dv[/tex]

=∫[tex]\frac{u+1}{2u(u-1)}du[/tex]

=[tex]\frac{1}{2}[/tex]∫[tex](\frac{2}{u-1} -\frac{1}{u} )du[/tex]

=[tex]ln(u-1)-\frac{ln(u)}{2} +c[/tex]

=[tex]ln(v^2-1)-\frac{ln(v^2)}{2}+c[/tex]

Right hand side:

[tex]=-ln(x)[/tex]

Solve for v:

[tex]v=-\frac{-c_{1}+\sqrt{c_{2}+4x^2 } }{2x} \ or \ \frac{-c_{1}+\sqrt{c_{2}+4x^2 } }{2x}\\[/tex]

[tex]y=\frac{-1}{2} \sqrt[]{4x^2+4c_{1}^2} -c_{1}\ or \ \frac{1}{2} \sqrt[]{4x^2+4c_{1}^2} -c_{1}[/tex]