Question

calcule :

 cotg 225 º ,sec 45 º ,cosec 30 º :

Answer 1

cos 225 / sen 225 = ...

225 - 180 = 45

cos 225 = - cos 45

cos 225 = -\/2/2

sen 225 = -\/2/2

 

tg 225 = 1

 

sec 45 = 1/cos 45 = 1/(\/2/2) = 2/\/2 = 2\/2/2 = \/2

 

cosec 30 = 1/sen 30 = 1/(1/2) = 2