Help With This Supposedly Easy Integration

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The integral of exp(sin(t)) / (1 + t^2) presents challenges for analytical solutions. Attempts at substitution, such as u=sin(t) and t=cos(u), lead to complex expressions that complicate integration. The integral arises from a differential equation dy/dt + y*cos(t) = 1 / (1 + t^2), for which an integrating factor of exp(sin(t)) was found. There is uncertainty about whether the integral can be solved analytically, with suggestions that it may need to be expressed in integral form. The possibility of an error in the problem statement is also raised, questioning the feasibility of finding an explicit solution.
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Homework Statement

Integrate: \exp(\sin(t)) / (1 + t^2)

The attempt at a solution
Ok so I tried substituting u=sin(t) du=cos(t)dt but I end up with (1 + arcsin^2(u)) on the bottom and I don't know how to integrate that.
I also tried letting t=cos(u) dt=-sin(u)du but then I end up with e^(sin(cos(t)) which I've never seen before!
If anyone knows how to do this please just give me a hint or the first step to take and I will try to do the rest! Thanks
 
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I don't think you can integrate that analytically. Is this integral part of a larger problem?
 
Ok well it was a differential equation problem that I reduced to that but here is the initial problem:

dy/dt + y\cos(t) = 1/ (1+t^2)

so I got an integrating factor of e^(sint) which led to this integral! Hope this helps maybe I did something wrong in first part.
 
Hmm, perhaps you're expected to leave the solution in terms of the integral.
 
I don't think so since the prof asked to solve it in terms of t explicitly. Maybe she made a mistake in writing the problem if this cannot be solved analytically.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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