NTA Abhyas JEE Main2020MathematicsLimitsPractice
The value of lim x → π tan π cos 2 x sin 2 2 x is equal to
Options
- A1
- Bπ
- C- π 4
- Dπ 2
Correct answer
C. - π 4
Step-by-step solution
Let, x = π + t lim t → 0 ⁡ tan ⁡ π cos 2 ⁡ π + t sin 2 ⁡ 2 π + 2 t = lim t → 0 ⁡ tan ⁡ π cos 2 ⁡ t sin 2 ⁡ 2 t = lim t → 0 ⁡ tan ⁡ π - π sin 2 ⁡ t sin 2 ⁡ 2 t = lim t → 0 ⁡ - tan ⁡ π sin 2 ⁡ t 4 π sin 2 ⁡ t cos 2 ⁡ t · π = - π 4