NTA Abhyas JEE Main2020MathematicsLimitsPractice
The value of l i m x → 0 ln 1 + 2 x + 4 x 2 + ln 1 - 2 x + 4 x 2 sec x - cos x is equal to
Options
- A- 1
- B1
- C0
- D4
Correct answer
D. 4
Step-by-step solution
l i m x → 0 ln 1 + 2 x + 4 x 2 + ln 1 - 2 x + 4 x 2 sec x - cos x = l i m x → 0 ln 1 + 4 x 2 2 - 4 x 2 1 - c o s 2 x / cos x = l i m x → 0 ln 1 + 4 x 2 + 16 x 4 sin x tan x = l i m x → 0 ln 1 + 4 x 2 1 + 4 x 2 4 x 2 1 + 4 x 2 4 x 2 1 + 4 x 2 ⋅ 1 sin x x ⋅ tan x x ⋅ x 2 = 4 a s l i m x → 0 ln 1 + x x = 1