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sgadi
 5 years ago
can someone solve int(e^x/(cos(x)))
sgadi
 5 years ago
can someone solve int(e^x/(cos(x)))

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Are you familiar with integration by parts?

sgadi
 5 years ago
Best ResponseYou've already chosen the best response.0yes ... but i am not able to solve using that ...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\int\limits_{?}^{?} udv = uv  \int\limits_{?}^{?} vdu\] What should we choose as our u and dv?

sgadi
 5 years ago
Best ResponseYou've already chosen the best response.0may be v=e^x and u=cos(x)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sure. Carry out integration by parts once. What do you end up with? (You should have an integral remaining on the right hand side that seems just as difficult to solve as this one. Leave it be for now)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Still there? You should end up with \[\int\limits\limits_{?}^{?}e ^{x}\cos x = e ^{x}\sin x  \int\limits\limits_{?}^{?}e ^{x}\sin x\] You would then perform integration by parts on the last term again, which will give you: \[\int\limits\limits_{?}^{?}e ^{x}\cos x = e ^{x}\sin x  (e ^{x}\cos x + \int\limits_{?}^{?}e ^{x}\cos x )\] Distribute the negateive, and move the integral term to the right hand side. Divide both sides by 2.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I thought he was trying to integrate \[\int\limits_{}e^x/cosx dx\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0...Guess that'll teach me to read the problem carefully. One moment to do the correct work.

sgadi
 5 years ago
Best ResponseYou've already chosen the best response.0the problem is \[\int{\frac{e^x}{\cos{x}}}\]

sgadi
 5 years ago
Best ResponseYou've already chosen the best response.0The actual problem I have is little more complex \[\int{\frac{e^{ax}}{\sqrt{b+c\cos{dx}}}}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0is the dx in the square root?

sgadi
 5 years ago
Best ResponseYou've already chosen the best response.0I am sorry ... \[\int{\frac{e^{ax}}{\sqrt{b+c\cos{(x)}}}dx}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0What level of math is this for? I'm having difficulty finding a way to make this clean...

sgadi
 5 years ago
Best ResponseYou've already chosen the best response.0I am working here to solve an model and got struck with this equation. It should be level of some master's engineering course.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well, I went ahead and used some software to examine the two deceptively simple looking integrals. The answer to the first involves a hypergeometric function, and it couldn't solve the second. Sorry, I don't think I'll be of much use to you on this.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well.... thats explains why I'm stummped

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\int\limits_{a}^{b}e^x/\cos x\] let u=e^x, du=e^x dx, dx=du/e^x so you have \[\int\limits_{a}^{b}du/cosx =\int\limits_{a}^{b} \sec x = \int\limits_{a}^{b}\ln \sec x + \tan x + C\] Hope this helps

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you cant do that because you have du/x, which means you have the change in u=du over cos(x), it has to either has to be du/u or dx/x or in the case of trig substitution dtheta/theta....... because of that your final answer lacks e^x and doesn't make sense
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