Sunday

April 20, 2014

April 20, 2014

Posted by **anonymous** on Tuesday, November 1, 2011 at 9:50am.

- university maths -
**drwls**, Tuesday, November 1, 2011 at 11:06amSee if this works:

http://www.math.colostate.edu/~gerhard/M345/CHP/ch2_6.pdf

It does not look like it meets the "exact differential" requirements

- university maths -
**Steve**, Tuesday, November 1, 2011 at 12:23pmGood reference. Try looking at the last example:

Substitute y = xv ⇒ dy = v dx+x dv

(xy-y^2)dx - (x^2+xy)dy = 0

(x^2v - x^2v^2)dx - (x^2 + x^2v)(vdx + xdv) = 0

2/x dx + (1+v)/v^2 dv = 0

2lnx + (lnv - 1/v) = C

ln(x^2v) - 1.v = C

vx^2 = Cexp(1/v)

y = vx

xy = Ce^{x/y}

Check my math, as always.

- university math -
**drwls**, Tuesday, November 1, 2011 at 10:04pmI want to congratulate and thank Steve for that very impressive solution.

**Related Questions**

Mathematics - Solve the following differential equation, i.e. solve for y: dy/dx...

Calculus - I am unsure of how to take the derivative of this equation. It may be...

math- differential equations - This is what im given (1 + x)dy/dx - xy = x + x2 ...

differential equations - the directions are to determine whether or not the ...

Math, Calculus - help Please... Differential Equations Problems... please give ...

Match, Calculus - help Please... Differential Equations Problems... please give ...

Math - help Please... Differential Equations Problems... please give the ...

calc - 1 + x = sin(xy^2) find dy/dx by implicit differentiation 0 + 1 = cos(xy^2...

calculus - a particle moves along the curve xy=10. if x=2 and dy/dt=3, what is ...

Calculus - Use implicit differentiation to find dy/dx if cos xy = 2x^2 - 3y. I'm...