NTA Abhyas JEE Main2020MathematicsLimitsPractice
The value of lim x → 2 π cos x - cos x cos x 1 - cos x + ln cos x is equal to
Correct answer
2
Step-by-step solution
Let, L = l i m x → 2 π cos ⁡ x - ( cos ⁡ x ) cos ⁡ x 1 - cos ⁡ x + ln ⁡ cos ⁡ x Putting cos ⁡ x = t , we get, L = lim t → 1 ⁡ t - t t 1 - t + ln ⁡ t Now by L-Hospital rule L = l i m t → 1 1 - t t ( 1 + ln ⁡ t ) - 1 + 1 t Again by L-Hospital rule = l i m t → 1 - t t 1 t - t t 1 + ln ⁡ t 2 - 1 t 2 = 2