NTA Abhyas JEE Main2020MathematicsTrigonometric EquationsPractice
The total number of solutions of the equation sin ⁡ x tan ⁡ 4 x = cos ⁡ x for all x ∈ 0 , π are
Correct answer
5
Step-by-step solution
tan 4 x = cot x = tan π 2 - x 4 x = n π + π 2 - x 5 x = n π + π 2 = 2 n + 1 π 2 ⇒ x = 2 n + 1 π 10 x = π 10 , 3 π 10 , 5 π 10 , 7 π 10 , 9 π 10 Hence, 5 solutions in 0 , π