Derivative of CAS

[HubbaBubba]

how do I get f'(pi) when f(x)=2cos^2(x/4)+1. Doing these types of problems by hand is no problem but in an exam its better not to waste time. The bit where it says ^2(x/4) is not joined, it is only to the power of 2. I keep getting the error Missing (.

[theshunpo]

You must not be putting brackets around the whole cos(x/4) then squaring it.
In the image attached f(x) is how to define it.
g(x) on the other hand is when you get the error

Edit: I assumed you meant Ti-Nspire, hope it helps

[HubbaBubba]

IT WORKED!!!

THANKS SO MUCH theshunpo