Question

give the equivalent fundamental identities of each functions:
sin,cos,tan,csc,sec,tan

Answer 1

There are so many identities for these. I am not sure which ones are the fundamental identities.
tanx=sinx/cosx
secx=1/cosx
csecx=1/sinx

Answer 2

maybe sin^2x+cos^2x=1

Answer 3

http://www.sparknotes.com/math/trigonometry/trigonometricidentities/section1.html
lists all 8.