Question

How do you verify `(1+cos2x)/(sin2x) = cotx`?

Answer 1

Since

`cos2x=cos^2x-sin^2x=1-2sin^2x=2cos^2x-1`

and

`sin2x=2sinxcosx`

then:

`(1+2cos^2x-1)/(2sinxcosx)=cotxrArr`

`(2cos^2x)/(2sinxcosx)=cotxrArr`

`cosx/sinx=cotxrArr`

`cotx=cotx`.