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STATEMENT-1 : lim(x->oo)(log[x])/([x])=0...

STATEMENT-1 : `lim_(x->oo)(log[x])/([x])=0`. STATEMENT-2 : `lim_(x->0)(sqrt(sec^2-1))/x` does not exist. STATEMENT-3: `lim_(x->2)(x-1)^(1/(x-2)) = 1`

A

TTT

B

TTF

C

FTF

D

FFF

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given statements, we will analyze each statement one by one. ### Statement 1: **Evaluate**: \(\lim_{x \to \infty} \frac{\log[x]}{[x]}\) 1. **Understanding the components**: - \(\log[x]\) refers to the logarithm of the greatest integer function of \(x\), which is denoted as \(\log(\lfloor x \rfloor)\). - \([x]\) is the greatest integer less than or equal to \(x\), denoted as \(\lfloor x \rfloor\). 2. **Behavior as \(x \to \infty\)**: - As \(x\) approaches infinity, \(\lfloor x \rfloor\) also approaches infinity. - Thus, both the numerator and denominator approach infinity. 3. **Applying L'Hôpital's Rule**: - Since both the numerator and denominator approach infinity, we can apply L'Hôpital's Rule: \[ \lim_{x \to \infty} \frac{\log(\lfloor x \rfloor)}{\lfloor x \rfloor} = \lim_{x \to \infty} \frac{\frac{d}{dx}(\log(\lfloor x \rfloor))}{\frac{d}{dx}(\lfloor x \rfloor)} \] - The derivative of \(\lfloor x \rfloor\) is 0 almost everywhere, but we can consider the behavior of \(\log(\lfloor x \rfloor)\) as \(x\) becomes very large. 4. **Conclusion**: - Since \(\log(\lfloor x \rfloor)\) grows much slower than \(\lfloor x \rfloor\), we find that: \[ \lim_{x \to \infty} \frac{\log(\lfloor x \rfloor)}{\lfloor x \rfloor} = 0 \] - Therefore, **Statement 1 is true**. ### Statement 2: **Evaluate**: \(\lim_{x \to 0} \frac{\sqrt{\sec^2 x - 1}}{x}\) 1. **Simplifying the expression**: - We know that \(\sec^2 x - 1 = \tan^2 x\), hence: \[ \sqrt{\sec^2 x - 1} = \sqrt{\tan^2 x} = |\tan x| \] 2. **Limit as \(x\) approaches 0**: - Thus, the limit becomes: \[ \lim_{x \to 0} \frac{|\tan x|}{x} \] - As \(x\) approaches 0, \(\tan x \approx x\), so: \[ \lim_{x \to 0} \frac{|\tan x|}{x} = \lim_{x \to 0} \frac{x}{x} = 1 \] 3. **Conclusion**: - Since both the left-hand limit and right-hand limit yield the same result, the limit exists. - Therefore, **Statement 2 is false**. ### Statement 3: **Evaluate**: \(\lim_{x \to 2} (x-1)^{\frac{1}{x-2}}\) 1. **Rewriting the expression**: - We can rewrite the limit as: \[ \lim_{x \to 2} e^{\frac{\log(x-1)}{x-2}} \] 2. **Finding the limit of the exponent**: - As \(x\) approaches 2, both \(\log(x-1)\) approaches \(\log(1) = 0\) and \(x-2\) approaches 0. - This is an indeterminate form \(\frac{0}{0}\). 3. **Applying L'Hôpital's Rule**: - We apply L'Hôpital's Rule: \[ \lim_{x \to 2} \frac{\log(x-1)}{x-2} = \lim_{x \to 2} \frac{\frac{1}{x-1}}{1} = \frac{1}{2-1} = 1 \] 4. **Conclusion**: - Therefore, the limit becomes: \[ e^1 = e \] - Hence, **Statement 3 is false**. ### Final Summary: - **Statement 1**: True - **Statement 2**: False - **Statement 3**: False
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Knowledge Check

  • lim_(x to 2)(log(x-1))/(x-2) is equal to

    A
    A. 0
    B
    B. `-1`
    C
    C. `1/2`
    D
    D. 1
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