JEE Main202117 Mar 2021Morning ShiftMathematicsMatricesActual
If A = 0 sin α sin α 0 and det A 2 - 1 2 I = 0 , then a possible value of α is
Options
- Aπ 2
- Bπ 3
- Cπ 4
- Dπ 6
Correct answer
C. π 4
Step-by-step solution
A 2 = sin 2 α I So, A 2 - I 2 = sin 2 α - 1 2 2 = 0 ⇒ sin α = 1 2 ⇒ α = π 4