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# Differential equation question

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1. Hi guys,Could someone help me with finding the solution to dy/dx = x + xy (You don't need to make y the subject) The answer is ln (1+y) = x^2/2 +c I can see how the answer is the above (using differentiation) but can't seem to find how to go the other way. Thanks!!
2. You can rewrite as . Do you know where to go from there?
3. (Original post by NeverLucky)
You can rewrite . Do you know where to go from there?
Oh my goodness, I just saw it. I would separate the variables into
1/(1+y) . dy = x . dx

and then integrate each side to get
ln (1+y) = x^2/2 + c

Thank you for your help! By the way, how did you format the equations so it looks nicer?
4. (Original post by dyuunn)
Oh my goodness, I just saw it. I would separate the variables into
1/(1+y) . dy = x . dx

and then integrate each side to get
ln (1+y) = x^2/2 + c

Thank you for your help! By the way, how did you format the equations so it looks nicer?
Yep, well done. It's using LaTex to write the equations. There's a page on TSR showing how to write in LaTeX if you want to use it.
5. (Original post by NeverLucky)
Yep, well done. It's using LaTex to write the equations. There's a page on TSR showing how to write in LaTeX if you want to use it.
Awesome! Thank you once again.

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