Question
Question: \(2 \tan ^ { - 1 } \frac { 1 } { 3 } + \tan ^ { - 1 } \frac { 1 } { 2 } =\)...
2tan−131+tan−121=
A
90∘
B
60∘
C
45∘
D
tan−12
Answer
tan−12
Explanation
Solution
2tan−131+tan−121=tan−1(1−9132)+tan−1(21)
=tan−1(9832)+tan−1(21)=tan−1(43)+tan−1(21)
=tan−1(1−21×4321+43)=tan−1(2).