NTA Abhyas 2020
- Exam
- NTA Abhyas
- Year
- 2020
- Subject
- Mathematics
- Chapter
- Limits
NTA Abhyas 2020 · Mathematics · Limits
The value of _ x → 0 (sec x + tan x) ^ (1)/(x) is equal to
The value of $\lim_{x \to 0}{\left(sec x + tan x\right)}^{\dfrac{1}{x}} is equal to
Options
- A
- B
- C
- D
Correct answer
A.
Step-by-step solution
( form)
= e^{\lim_{x \to 0}\dfrac{1}{x}\left(sec x + tan x - 1\right)} = e^{\lim_{x \to 0}\left(\dfrac{1 + sin x - cos x}{xcos x}\right)} = e^{\lim_{x \to 0} \left(\dfrac{\text{ cos } x +\text{ sin } x}{-\text{ xsin } x +\text{ cos } x}\rright)}\left(byL ' Hospitalrule\right)e\dfrac{1 + 0}{0 + 1} =
= e^{\lim_{x \to 0}\dfrac{1}{x}\left(sec x + tan x - 1\right)} = e^{\lim_{x \to 0}\left(\dfrac{1 + sin x - cos x}{xcos x}\right)} = e^{\lim_{x \to 0} \left(\dfrac{\text{ cos } x +\text{ sin } x}{-\text{ xsin } x +\text{ cos } x}\rright)}\left(byL ' Hospitalrule\right)e\dfrac{1 + 0}{0 + 1} =