sec(-x)cotx
put secx=1/cosx
and cotx=cosx/sinx
=> -(1/cosx)*(cosx/sinx)
=> -(1/sinx)
put 1/sinx=cosecx
=> -cosecx
So Sec(-x)cot x = -cosec x
Cheers
and cotx=cosx/sinx
=> -(1/cosx)*(cosx/sinx)
=> -(1/sinx)
put 1/sinx=cosecx
=> -cosecx
So Sec(-x)cot x = -cosec x
Cheers