NTA Abhyas JEE Main2020MathematicsInverse Trigonometric FunctionsPractice
The value of a for which a x 2 + sin - 1 ⁡ x 2 - 2 x + 2 + cos - 1 ⁡ x 2 - 2 x + 2 = 0 has a real solution, is
Options
- A- 2 π
- B2 π
- C- π 2
- Dπ 2
Correct answer
C. - π 2
Step-by-step solution
Here, x 2 - 2 x + 2 = x - 1 2 + 1 ≥ 1 But, - 1 ≤ ( x 2 - 2 x + 2 ) ≤ 1 Which is possible only when x 2 - 2 x + 2 = 1 ⇒ x = 1 Then, a 1 2 + sin - 1 1 + cos - 1 1 = 0 ⇒ a + π 2 + 0 = 0 ⇒ a = - π 2