NTA Abhyas JEE Main2020MathematicsTrigonometric EquationsPractice
The solution of the equation sin 2 x + cos 2 3 x = 1 is
Options
- Ax = n π 3
- Bx = n π + π 4
- Cx = n π 4
- Dx = n π + π 2
Correct answer
C. x = n π 4
Step-by-step solution
sin 2 x = 1 - cos 2 3 x = sin 2 3 x sin 2 3 x - sin 2 x = 0 sin 4 x sin 2 x = 0 sin 2 x = 0 ⇒ 2 x = n π ⇒ x = n π 2 or sin 4 x = 0 ⇒ 4 x = n π ⇒ x = n π 4 ⇒ x = n π 4