Question

In a triangle ABC, If tan A/2=5/6
and tan C/2=2/5,then show that a,b,c in are in A.P.​

Answer 1

Answer:

TanA/2.tan C/2=1/3

3[Delta ^2] /s^2 (s-a) (s-c) =1

3[s-b]/=s

2s=3b

a+b+c=3b

a+c=2b

Therefore a, b, c are in A. P.