my name is Dimos and I am coming from Greece.
Right to the point.
1) Can somebody help me with the:
I ve tried to find a integration factor and change variable (e.g. v=2x*cos(y) ). I have no clue! Is this ODE a suitable example for polytechnics student?
2) Is there any higher order derivative test to find extrema of multi variable functions? Where can i find more details?
3) Can the use of Lagrange multipliers reveal the nature of extrema (i.e. is it a local minimum, local maximum or saddle point)? How?
Thank you in advance for any help!