tan^-1 1/11 + tan^-1 2/11 is equal to A. 0 B. 1/2 C. -1 D. none of these

Question

tan^-1\(\frac1{11}\) + tan^-1\(\frac2{11}\) is equal to

 A. 0

B. \(\frac1{2}\)

C. -1

D. none of these

Answer 1

Correct option is D. none of these

We need to find the value of

 tan^-1\(\frac1{11}\) + tan^-1\(\frac2{11}\) 

Using property of inverse trigonometry,

Thus, none of this match the result.