Exact Solution for Integral of sin(x)/(10x+1) without Taylor Series?

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Homework Statement



The problem: finding an exact result (or at least a method for computing the exact result) of

\int_0^5 \frac{sin(x)}{10x-1} dx

Homework Equations



Is there any way to solve this integral other than using Taylor series?

The Attempt at a Solution



= \int_0^5 \sum_{i=0}^{\infty} \frac{(-1)^ix^{2i+1}}{(2i+1)!(10x+1)}dx
 
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eric222 said:

Homework Statement



The problem: finding an exact result (or at least a method for computing the exact result) of

\int_0^5 \frac{sin(x)}{10x-1} dx

Homework Equations



Is there any way to solve this integral other than using Taylor series?

The Attempt at a Solution



= \int_0^5 \sum_{i=0}^{\infty} \frac{(-1)^ix^{2i+1}}{(2i+1)!(10x+1)}dx

Hmm... let's try something...

\int_0^5 \frac{sin(x)}{10x-1} dx

u = x - 1/10

\int_{-.1}^{4.9} \frac{sin(u+.1)}{10u} dx

Whatever happens, though, it won't be an elementary integral, I'll tell you that right now. You can split the sin(u+.1) using the addition formula sin(x+y) = sin(x)cos(y) + cos(x)sin(y), but it won't be elementary.
 
Last edited:
Do you mean finding the principle value of this integral? What happens at x = 1/10...
 
quZz said:
Do you mean finding the principle value of this integral? What happens at x = 1/10...

How stupid of me. I should have noticed this directly.

Thanks for the help, everyone!
 
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