If cos (A + B) / cos (A - B) = cos 2C ,

Question

then tan A , tan C , tan b are in which progression? 

PLEASE SHOW THE STEPS CORRECTLY. the options are - 

a) AP 

b) GP 

c) HP 

d) none of these

 

 

 

Answer 1

 

If

Substitute the cos(2C) formula in terms of tan.

Therfore tanA, tanC and tanB are in G . P

Option b is correct choice.