Read the following text and and answer the following questions on the basis of the same :
In the school project Sheetal was asked to construct a triangle and name it as ABC. Two angles A and B were given to equal to `tan^(-1)""(1)/(2)` and `tan^(-1)""(1)/(3)` respectively.

If `B=cos^(-1)x`, then x = _______.

Options

A. `(1)/(sqrt5)`
B. `(3)/(sqrt(10)`
C. `(1)/(sqrt10)`
D. `(2)/(sqrt5)`

Answer

B