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# C4 growth and decay

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1. Need a hand on 4ci no idea what ive done aha
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2. Divide by (15-x)
Then integrate LHS with respect to x and RHS with respect to to as normal with differential equations.
3. Your working in scan 2 is almost there. Refer back to the original equation and write your exponential term as a function of x.
4. (Original post by nerak99)
Your working in scan 2 is almost there. Refer back to the original equation and write your exponential term as a function of x.
Thanks for the hint figured it out aha im such an idiot lol
5. (Original post by Mitul106)
Need a hand on 4ci no idea what ive done aha
Rearrange the initial equation to get t in terms of x so you are left with a function of x. Then differentiate to find out what dt/dx is. After you have, then just flip it to get your answer.

EDIT: Just saw that you figured it out. What I have said is a separate method you can do if you want to.

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