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anonymous
 5 years ago
Integral of 1 / ( 1 + e ^ x) actual process please... :D
anonymous
 5 years ago
Integral of 1 / ( 1 + e ^ x) actual process please... :D

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Dang you got 103 fans now!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Hi arman, Try looking at it like this\[\int\limits_{}{}\frac{1}{1+e^x}dx=\int\limits_{}{}\frac{1+e^xe^x}{1+e^x}dx=\int\limits_{}{}1\frac{e^x}{1+e^x}dx\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[=x\log (1+e^x) + c\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0log == ln always unless a base is made explicit

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0It's an arctrig function and xln(1+e^x) is e^x/(1+e^x) (chain rule)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0II know that it's arctan of something ><

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The second integral makes use of this fact:\[\int\limits_{}{}\frac{f'(x)}{f(x)}dx=\log f(x)+c\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0If f(x)=1+e^x, then f'(x)=e^x, which is the form you have after rearranging.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I'm on my fone so I didn't see half of those equations till after I posted my last post.... lemmy try that... yummy and sec

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0u substitution then partial fraction decomposition

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I don't get why I can't think of these on my own .

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i got an answer of ln(e^x/(e^x+1))+c

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0There's one way to check your answer  take the derivative and see if you get back to the integrand.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Nope, pfd is in the chapter after this (I slipped it previousy and went ahead) so Lucas answer makes perfect sense...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oh boy, integral of e^sqrtx from 0 to 4...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I don't even know what to use on this one...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.02(e^(sqrt(x))(sqrt(x)1)(0,4)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0have u learned integration by parts yet?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0and i take it you know u substitution?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0start with your integral and set u equal to sqrt(x)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0u should get int(2u(e^u)du)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0do you follow me so far?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You can put the dx in terms of u aswell? (Like I can write 2u instead of 2sqrtx? )

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0from this point you can use integration by parts

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ok then that makes sense and i can use the uv vdu then.... . I'm retarded

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol its hard to see that without substituting first tho

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0No... I'm just retarded. And the answer is 2e^2

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0did u evaluate at zero also?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Good point, further testing my retardation.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0When you uv vdu sub, can you choose which term is your u and v? I'm pretty sure you can

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0usually it depends on what you have

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0to remember what to take for u i use "lipet"

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0which gives you an order in which to take your u (Lograthims Inverse.trg Polynomials Exponetials Trigonometrics)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well I got a badass equation here: integral of (lnx) /x^2 from 1 to 2

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I know I gotta use uv vdu on it

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0judging by lipet take log to be your u

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0and 1/x^2 to be your dv

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0im getting (ln(x)/x)(1/x)+c

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0your evaluated integral should come out to be (ln(2)/2)+1/2

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0were you able to solve it?
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