Why can't I do this? (1 Viewer)

[Shuter]

HSC 2003 Question 1 a) FFS!!!

Integrate from 0-1

(e^x)
/
[(1+e^x)^2]

I tried by parts and it doesn't work, what the hell am I missing something blatently obvious?

 

[bladenia]

let u = e^x

 

[Rush152]

substitution!

let u= 1+e^x
u' = e^x


mmm there's something you're meant to do with the terminals but i forgot

 

[coca cola]

Its a straight forward rationalizing substitution. Remember d(e^x)/dx = e^x, and few other key ones include d(lnx)/dx = 1/x, d[sqrt f(x)]/dx = f'(x)/[2sqrt f(x)]

 

[Shuter]

Thank you yes it's u = (e^x) + 1 not simply e^x.

But I got:

-1
/
(e+1)

as my answer, but is this guy wrong?
http://www.boredofstudies.org/courses/maths/4u/2003_Mathematics_Extension_2_HSC_Sol_Jeff_Geha.pdf

It seems like he forgot to change his limits.

 

[Rorix]

e^0 = 1


i am now writing words because i need to fill it up to ten

 

[Shuter]

Oh bloody hell, I did that and found the new limit was 2 but then wrote it down as being 0 for no good reason, god damnit.

 

[funk_master81]

i think its x^e(1)

 

[Shuter]

Answer is
(e-1)/
[2(e+1)]

Thank god I finally got it.