How do you simplify #cos(arctan(x)) #?
We need to have an expression for
\0/ Here's our answer !
Continuation of my first answer that was edited by another.
Let a = arctan ( x ).
The principal value of
previous answer, two years ago).
Now, the given expression is
It is important that
If the piecewise-wholesome general inverse operator
the negative sign is chosen, when
So, the value is
My intention, in this approach, is to inform about nuances..
So, I am making a second answer,