Nice video here of your problem
https://www.youtube.com/watch?v=V3FoNfYstNk
calculate differentiation of cos x to x using first principle of derivative. Find the value of differentiated function , if x = 270°
4 answers
cos x to x ?
not cos x
what about this x = 270°?
not cos x
what about this x = 270°?
cosxsinxcosx
cosxsinxcosx