NTA Abhyas JEE Main2020MathematicsInverse Trigonometric FunctionsPractice
The value of 2 cos - 1 2 3 - 2 cos - 1 6 + 1 2 3 is equal to
Options
- Aπ 3
- Bπ 4
- Cπ 2
- Dπ 6
Correct answer
A. π 3
Step-by-step solution
2 c o s - 1 2 3 - 2 c o s - 1 6 + 1 2 3 = 2 t a n - 1 1 2 - 2 t a n - 1 3 - 2 1 + 6 = 2 t a n - 1 1 2 - 2 t a n - 1 3 - t a n - 1 2 = 2 t a n - 1 1 2 + t a n - 1 2 - 2 tan - 1 ⁡ 3 = π - 2 π 3 = π 3