anyone know anything about 2nd order differential equations?!? yes, they really are as fun as they sound ... anyway, if there are any super duper maths whiz's out there then pletty please try this one ... Find a suitable intergrating factor to solve: x(dy/dx) + 3y = (e^x) /(x^2) think i must be using the wrong integrating factor thingy... :-? aaargh why would anyone do maths?!?! merci x

it sounds like i should know what you're on about... having just done differential type stuff in AS maths... but i haven't a clue what your formula thingy is... sorry.. i am of no use whatsoever.

i aint got a clue, but i av asked some mated but they said they did back in high school and cant remember how to do it. sorry

The integrating factor First order differential equations of this form:. where P and Q are functions of x only, can be solved by use of an integrating factor, I where: By using the integrating factor, the differential equation can be changed into an exact differential equation. This is a differential equation where the main part of it is the exact derivative of a product, and the rest is easy to integrate. check out this website http://www.mathsnet.net/asa2/2004/fp15intfact.html

Hi, I know I'm probably missing something but is that equ. not first order? Don't you need a y" ( not just y' ) for a 2nd order, where you then get the auxiliary equation and complementary function? :-? Also Lottie, is that right? Intergral of (f(x)/g(x)) isn't equal to int. f(x) / int. g(x). Sorry if this is all nonsense, only just up

Maths used to be fun when it was just numbers. As soon as they started trying to make me count letters as well I lost the will to live.

In the words of hitler upon finding out that the russians where pretty close to taking over berlin.. EH?!

Your LHS works out as (1/x^2) d/dx{x^3 y}. You can solve it from there. The "a level" formulaic way is to get it in the form dy/dx + f(x) y = For yours, that would by dy/dx + 3/x y = (by dividing by x) Integrating factor is then R = e^{int 3/x dx} It's still only first order, though.

Thanks guys! have done it (i think :-? ) so thank you kindly to all you super clever lovely people xx