cos A= sen B
cot (-A) =- cot (A)
csc (-A) =- csc (A)
tan^2 A + 1= sec^2 A
cot A= tan B
tan (-A) =- tan (A)
tan A cot A=1
sen (-A) =- sen (A)
tan A= cot B
cot^2 A + 1= csc^2 A
sec A= csc B
sec (-A) = sec (A)
csc A= sec B
Tan A = sen A / cos A
cos A sec A=1
sen A= cos B
sen A csc A=1
cot A = cos A / sen A
sen^2 A + cos^2 A=1
cos (-A) = cos (A)
