Integration/calc work? what did i do wrong

Thread starter badtwistoffate
Start date Sep 25, 2005
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AI Thread Summary

The discussion revolves around the integration of the function 1/(x^2+4)^2 using the substitution x = 2 tan(q). The user transforms the integral but struggles with the subsequent steps, particularly in simplifying the expression and considering a u-substitution with tan(q) = u. There is confusion about the correctness of the transformation and whether the proposed substitution is valid. The user expresses frustration about not receiving help on their topic. The thread highlights challenges in integration techniques and the importance of proper substitution methods in calculus.

Sep 25, 2005

badtwistoffate

Int[1/(x^2+4)^2]
let x= 2 tan(q)
i get 1/(4 tan^2(q) + 4)^2
I get 1/ (16 tan ^4(q) + 32 (1-sec^2(q) + 16)
and now i think about doing a u-substituition with tan x=u, du =sec^2 (x) can i do that!?!

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Sep 25, 2005

badtwistoffate

do you just don't like my topics i want help in?

Sep 25, 2005

whozum

\frac{1}{(4\tan(q)+4)^2} = \frac{1}{16\sec^4q}

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