Question:

lim(x→0)\((\frac {1+tanx}{1+sinx})^{cosec x}\) = ?

Updated On: Aug 26, 2024
  • 0
  • e
  • 1
  • \(\frac {1}{e}\)

Hide Solution
collegedunia
Verified By Collegedunia

The Correct Option is C

Approach Solution - 1

Let's consider the limit as x approaches 0: 
lim(x→0) \((\frac {1+tanx}{1+sinx})^{cosec x}\) as x approaches 0 
Substituting x = 0 into the expression gives us: 
\((\frac {1+tan(0)}{1+sin(0)})^{cosec (0)}\)
Since tan(0) = 0 and sin(0) = 0, we have: 
\((\frac {1+0}{1+0})\)(cosec 0) 
Simplifying further: 
1(cosec 0) 

Therefore, the correct option is (C) 1.

Was this answer helpful?
1
1
Hide Solution
collegedunia
Verified By Collegedunia

Approach Solution -2

\(\lim_{x \to 0} \left( \frac{1 + \tan x}{1 + \sin x} \right)^{\cosec x}\)

we can use approximations and simplifications. Here's a streamlined approach:

Approximate tan x and sin x for small x:
\(\tan x \approx x\)
\(\sin x \approx x\)

Rewrite the expression using these approximations:
\(\frac{1 + \tan x}{1 + \sin x} \approx \frac{1 + x}{1 + x} = 1\)

Consider the entire expression:
\(\left( \frac{1 + \tan x}{1 + \sin x} \right)^{\cosec x} \approx 1^{\cosec x}\)

Note that \(\cosec x = \frac{1}{\sin x}\), and for small x, \(\sin x \approx x\):
\(\cosec x \approx \frac{1}{x}\)

Substitute \(\cosec x \approx \frac{1}{x}\) into the expression:
\(1^{\cosec x} \approx 1^{\frac{1}{x}}\)

Recognize that 1 raised to any power is still 1:
\(1^{\frac{1}{x}} = 1\)

So, the correct option is (C): 1

Was this answer helpful?
0
0

MHT CET Notification

Concepts Used:

Limits of Trigonometric Functions

Assume a is any number in the general domain of the corresponding trigonometric function, then we can explain the following limits.

Limits of Trigonometric Functions

We know that the graphs of the functions y = sin x and y = cos x detain distinct values between -1 and 1 as represented in the above figure. Thus, the function is swinging between the values, so it will be impossible for us to obtain the limit of y = sin x and y = cos x as x tends to ±∞. Hence, the limits of all six trigonometric functions when x tends to ±∞ are tabulated below: