Prove that


To Prove: cot - tan = 2cot x


Proof: Consider L.H.S,


cot - tan -


=


= ()



Here multiply and divide L.H.S by 2


=


= (2sinxcosx = sin2x)


()


cot - tan = 2cotx = R.H.S


L.H.S = R.H.S, Hence proved


2