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# Differential equations with ln watch

1. Hello
just wanted to check a rule - when you have something where you take ln of both sides do you also take ln of the constant of integration?

example:
I started with

I know this is the answer from the sheet, just not sure if this is how you get to it?

2. It's correct but to go through it bit by bit you need an extra line of working

From

3. What is this I don't even
4. What you did is fine. It doesn't matter what you do with the constant of integration; if you wrote instead of then it'd be fine, but when you go to simplify you'd get . However, since is just an arbitrary constant, so is , so writing you'd have (which is the same as you have, just with C relabelled as A).
5. (Original post by nuodai)
What you did is fine. It doesn't matter what you do with the constant of integration; if you wrote instead of then it'd be fine, but when you go to simplify you'd get . However, since is just an arbitrary constant, so is , so writing you'd have (which is the same as you have, just with C relabelled as A).
Brilliant thanks for the help guys, I need to spread rep around before repping again.

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