Q Prove the following (iii) tan-123=12tan-1125 - Maths - Inverse Trigonometric Functions

Question

Q Prove the following
(iii) tan - 1 2 3 = 1 2 tan - 1 12 5

Md.Ashraf Khan · Accepted Answer

Using Standard Result2tan-1θ = tan-12θ1-θ2Here θ = 232tan-123 = tan-12
231-232 =  tan-1431-49 =  tan-14359 = tan-1125

Q. Prove the following (iii) tan - 1 2 3 = 1 2 tan - 1 12 5