
tanh(x)
I'm trying to prove:
Here's what I've done so far:
From this point I'm not sure what to do. I know of the identities:
However, even with these in mind, I've been trying this for ages to no avail. Can someone give me some pointers?
Thanks

Hello,
But this is false !
It's a multiplication, not an addition.
will give you what you wrote, but the multiplication will give :
(you can simplify by 2) :
But I'd suggest you use these formulae :
Hence
Divide both numerator and denominator by (Wink)

Ahh, such as stupid mistake, I've been looking at it so long I missed it. (Giggle)
Thanks alot!

Ok, now I'm trying to prove:
Any ideas? I'm not sure if this is even right, it was after an integration of

Hello, Greengoblin!
This is not true . . .
.

Hi Soroban, I suspected as much, since I was getting that same expression in trying to simplify. It must be a problem with my integration then. I used the substitution , and I think my mistake was taking the out of the integral, which can't be done.
Is there some easier substitution I can make?

Hi, no worries, I've cracked it now...proved that the derivative of sinhx is coshx, therefore the integral of coshx is sinhx. Thanks for the help though!