Question

demostrar que sec a * csc a = tan a + cot a

Answer 1

 Tan a+ Cot a = Sec a * Csc a 
Cos a/Sen a + Sen a/ Cos a
Cos^ 2 a + Sen^2 a/ Sen a * Cos a
1/ Sen a * Cos a
1/ Sen a * 1/ Cos a
= Sec a * Csc a