I was doing this equation and I used the substitution which gave me
which simplifies to but i cant see how the first term of this was obtained from the first line here. If some one could help youd be od great help!!!
If we let
Then we get
(1)
So now seeing that
We can rewrite (1) as
Now backsubbing
Gives us
Now you really should know that
So using that we may further rewrite (1) as
(2)
So now you asked
Now by the sub
We obtain
So now using (2) we see that this is equivalent to
Now backsubbing finally gives
That is about as drawn out and forward as I can be. If you still dont get it, I am not sure I can help