Take the 2-minute tour ×
Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

I was told to solve this without integration and to use implicit diffentiation.

$$x^3 y^{\prime} - \dfrac{3y}{x} = x^3 e^{\left(x - \dfrac{1}{x^3}\right)}$$

I am utterly lost, any suggestions.

I can get to

$$ x^4y^{\prime} - 3y = x^4 e^{\left(x - \dfrac{1}{x^3}\right)}$$

share|improve this question
    
@martin sleziak, any ideas? –  yiyi Nov 7 '12 at 6:52
    
@MartinSleziak, What is the difference between ode and differential-equations? –  yiyi Nov 7 '12 at 6:56
    
Most tags have tag-excerpt (which is displayed when you hover over the tag with you mouse) and tag-wiki. As you can read there, the differential-equations tag should be used for ordinary differential equations. I thought the correct tag was ode, which I remembered incorrectly. That's why I've edited your post twice. –  Martin Sleziak Nov 7 '12 at 7:00
    
@MartinSleziak I wasn't complaining, very happy with your edit, much better than changing ( to \left(. –  yiyi Nov 7 '12 at 9:20

1 Answer 1

up vote 1 down vote accepted

Hint: Multiply both sides by the integrating factor $e^{1/x^3}$.

share|improve this answer
    
what do you mean integrating factor? –  yiyi Nov 7 '12 at 10:54
    
en.wikipedia.org/wiki/… –  Hans Lundmark Nov 7 '12 at 11:11
    
I found an answer with wolfram alpha. But it needed to use integration. –  yiyi Nov 7 '12 at 12:29
    
If you're going to solve a differential equation, there's no way to avoid integration (definite or indefinite) at some stage... –  Hans Lundmark Nov 7 '12 at 16:32

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.