Section 4.4 Past Final Exam Question

[Jiayi Wang (Ivy)]

I was working on the 2019-FE-P3, for the Problem3 of the Deferred section, I got C1=10e^(-t)+10arctan(e^t)+C1, C2=-4e^(-2t)+4ln(e^(-2t)+1)+C2
The answer shows C1=10e^(-t)+5arctan(e^t)+C1, C2=-4e^(-2t)-4ln(e^(2t)+1)+C2.
I was wondering if anyone got the same answer with me, thanks very much.

[Qi An]

I get C1 = 10e^(-t) + 10arctan(e^t) + C1 and C2 = -4e^(-2t) + 4In|e^(2t)+1| + C2. I think there might be a typo here.

[Victor Ivrii]

There could be misprints