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anonymous
 5 years ago
integrate dx/9+4x^2
anonymous
 5 years ago
integrate dx/9+4x^2

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Seems like you want a trig substitution here. Something like let \(2x = 3tan(\theta)\)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well, what do you end up with using that substitution?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[ dx=3/2\sec ^{2}x thetad \theta\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yeah, though you have a stray x in there I'm assuming is a typo.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0So now convert your integral into the new form with respect to theta

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well, you have \[\int \frac{1}{9+4x^2}dx\] Since 2x = 3tan\(\theta\) What does that denominator become?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Which yes, then becomes \(9sec^2\theta\)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ok, now you said dx = (3/2)\(sec^2\theta\ d\theta\)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0So we have \[\frac{3}{2}\int\frac{sec^2\theta}{9sec^2\theta}d\theta\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0And I think you can take it from there.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yea i got it thx.............

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0polpak pls solve\[\int\limits \tan ^{3}x\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0polpak i need ur help

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Hrm.. I don't recall the strategy for powers of tan I'm afraid. I'll see if I can rederive it.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0chaguanas i know it but solve it

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0¬_¬ \[\int \tan^3x = \int \tan x \ (\sec^21) = \int \tan x\ \sec^2x  \int \tan x \]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0INewton pls continues

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0For the first one, you could use a substitution of note it is of the form \[f\ '(x) \cdot f \ (x) \] and try by recognition. \[ \int \tan x = \int \frac{\sin x}{\cos x}\] Which is of the form \[\frac{f \ '(x)}{f\ (x)} \] (think ln )

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0INewton pls solve \[\int\limits \sqrt{94x ^{2}}/x\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Same type deal as the other trig sub you had before except instead of tan you let 2x = \(3 sec\theta\)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Lets see if you can do it yourself this time.
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