# Homework Help: First order

1. Jul 9, 2014

### kyu

1. The problem statement, all variables and given/known data

2. Relevant equations

i have done till the 2nd final step
how is it possible to get the final answer y = -2x - 2/7 + ce^(-7x)
why is it ce^(-7x) and not c/e^(-7x)?

3. The attempt at a solution

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2. Jul 9, 2014

### Fredrik

Staff Emeritus
I agree with you. It should be $c/e^{-7x}=ce^{7x}$.

3. Jul 9, 2014

### Ray Vickson

You are correct.

4. Jul 9, 2014

### Orodruin

Staff Emeritus
While this was a quite blatant error where the last two lines were not compatible with each other. If you are in doubt, you can always insert the solution into the differential equation and check that it actually solves it.