Integration using inverse trig indentities?

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The discussion focuses on two integrals involving inverse trigonometric identities. For the first integral, participants suggest using the substitution u = cos(x) to simplify the expression, noting that a second substitution may not be necessary. The second integral requires completing the square in the denominator for easier integration. Attempts at u-substitution for the first integral yielded incorrect results, highlighting the complexity of the problem. Overall, the conversation emphasizes strategic substitutions and algebraic manipulation to solve the integrals effectively.
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Homework Statement


1.\int{\frac{sinx}{1+cos^{2}x}} \, dx
2.\int{\frac{1}{13-4x+x^2}} \, dx

Homework Equations


Inverse trig identities.

The Attempt at a Solution


For the first one, I'm not too sure about what to do with the sinx on the numerator and i have tried u-substitution to no avail (different answer). For the second one, I tried factorising but only had solutions for x\inℂ.
 
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You can maybe try to start with the substitution u = cos(x) and reforming the integral. A second substitution will be necessary after the first substitution.
 
eple said:
You can maybe try to start with the substitution u = cos(x) and reforming the integral. A second substitution will be necessary after the first substitution.
Second substitution is not necessary. It can be done in that first one.
 
For the second integral start by completing the square in the denominator.
 
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