I'm attaching the problem as a png. The top half is the question whereas the second half is the solution. I understand everything about the question until the ultimate answer(adsbygoogle = window.adsbygoogle || []).push({});

the final answer is: (r (constant) x0(constant) / k (constant)) * (1 - e^-60t)

as shown.

However I don't understand why my answer differs. I concluded the problem with

(r (constant) x0(constant) / k (constant)) * (-e^-60t)

This doesn't seem to be a basic algebra issue, and It is beyond my comprehension.

Thank you.

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# Homework Help: Quick question on exponential decay problem

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