Proving trig identities + Pre counter examples

[ianhendry]

Please help me prove this trig identity

{{{ (1-secx)/(1+secx) = (cosx-1)/(cosx+1) }}}

this is the middle of a section and they have turned up the gears, i think if i am shown how i will be able to figure the rest out.

[nona.m.nona]

Please help me prove this trig identity

{{{ (1-secx)/(1+secx) = (cosx-1)/(cosx+1) }}}

What did you get when you converted the left-hand side to sines and cosines, converted the fractions to common denominators, and simplified?