Solving ODE Problem: Tips and Techniques for Postgrad Students

  • Thread starter Thread starter dec46
  • Start date Start date
  • Tags Tags
    Ode
dec46
Messages
2
Reaction score
0
Hi All,

I am a postgrad student looking for help in solving this ODE.


Homework Statement



\frac{dy}{dx}=\frac{y^{2}+xy^{2}}{x^{2}y-x}


Homework Equations





The Attempt at a Solution


I have been attempting to solve this by substitution but without success, any help would be appreciated.

 
Physics news on Phys.org
It looks separable.
 
The furthest I can get is

x(xy-1)dy=(x+1)y^{2}dx

but do not know where to go from here?
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Back
Top