Hello Guys,

I don't know how to solve this:

t/ (racine) 1 + t^2 ==> for this i did this: ?

Thanks

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- Feb 3rd 2008, 07:23 AM #1

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- Feb 3rd 2008, 07:27 AM #2

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- Feb 3rd 2008, 08:20 AM #3

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- Feb 3rd 2008, 08:25 AM #4

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- Feb 3rd 2008, 08:34 AM #5

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- Feb 3rd 2008, 08:38 AM #6

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you did not substitute the limits in the correct order. and you also confused

$\displaystyle

\int \frac { \ln x}{x} dx= \frac{1}{2} (\ln x)^2 + C

$ for $\displaystyle

\int \frac { \ln x}{x} dx= \frac{1}{2} (\ln x)^x + C

$

also you should know that $\displaystyle \ln 1 = 0$ and $\displaystyle \ln e = 1$

- Feb 3rd 2008, 08:43 AM #7

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- Feb 3rd 2008, 08:53 AM #8

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- Feb 3rd 2008, 08:59 AM #9

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- Feb 3rd 2008, 09:05 AM #10

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- Feb 3rd 2008, 09:12 AM #11
Using many formulae for these problems, it's an incredibly bad idea.

These are routine problems, so we don't need formulae to make this work.

Substitute $\displaystyle u^2=1+t^2.$

(Correct english forms for $\displaystyle \sqrt{~~}$ and $\displaystyle \int$ are square root and integral.)

- Feb 3rd 2008, 09:18 AM #12

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- Feb 3rd 2008, 09:21 AM #13

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