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Match the following : {:("Column-I" , ...

Match the following :
`{:("Column-I" , " Column - II"), ("(A)" lim_(x to pi/4)(sin2x)^(tan^(2)2x), "(p)" 1/2),("(B)" lim_(x to oo) ((2x-1)/(2x+1))^(x) , "(q)"e^(-1/2)),("(C)" lim_(x to pi/2)(tanx)^(tan 2x) , "(r)" e^(-1)),("(D)" lim_(x to pi/4) tan2x tan(pi/4-x), "(s)" 1):}`

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To solve the problem of matching the limits from Column-I with their corresponding values in Column-II, we will analyze each limit step by step. ### Step 1: Evaluate Limit A **Limit A:** \[ \lim_{x \to \frac{\pi}{4}} (\sin 2x)^{\tan^2 2x} \] 1. Substitute \(x = \frac{\pi}{4}\): \[ \sin 2\left(\frac{\pi}{4}\right) = \sin \frac{\pi}{2} = 1 \] \[ \tan 2\left(\frac{\pi}{4}\right) = \tan \frac{\pi}{2} \text{ (undefined, but we analyze the limit)} \] 2. This gives us the form \(1^{\infty}\). We can use the logarithmic limit: \[ y = (\sin 2x)^{\tan^2 2x} \implies \ln y = \tan^2 2x \cdot \ln(\sin 2x) \] 3. As \(x \to \frac{\pi}{4}\), \(\tan^2 2x \to \infty\) and \(\ln(\sin 2x) \to 0\). We rewrite: \[ \lim_{x \to \frac{\pi}{4}} \tan^2 2x \cdot \ln(\sin 2x) \] 4. Using L'Hôpital's Rule or Taylor expansion, we find: \[ \lim_{x \to \frac{\pi}{4}} \tan^2 2x \cdot \ln(\sin 2x) = -\frac{1}{2} \] 5. Therefore, \[ \lim_{x \to \frac{\pi}{4}} (\sin 2x)^{\tan^2 2x} = e^{-\frac{1}{2}}. \] This corresponds to option **(q)**. ### Step 2: Evaluate Limit B **Limit B:** \[ \lim_{x \to \infty} \left(\frac{2x-1}{2x+1}\right)^{x} \] 1. Rewrite the expression: \[ \frac{2x-1}{2x+1} = 1 - \frac{2}{2x+1} \] 2. As \(x \to \infty\), this approaches \(1\), leading to the form \(1^{\infty}\). 3. Using the logarithmic limit: \[ \ln y = x \ln\left(1 - \frac{2}{2x+1}\right) \approx -\frac{2x}{2x+1} \text{ (using Taylor expansion)} \] 4. This simplifies to: \[ \lim_{x \to \infty} -\frac{2x}{2x+1} = -1 \] 5. Therefore, \[ \lim_{x \to \infty} \left(\frac{2x-1}{2x+1}\right)^{x} = e^{-1}. \] This corresponds to option **(r)**. ### Step 3: Evaluate Limit C **Limit C:** \[ \lim_{x \to \frac{\pi}{2}} (\tan x)^{\tan 2x} \] 1. Substitute \(x = \frac{\pi}{2}\): \[ \tan\left(\frac{\pi}{2}\right) \to \infty \quad \text{and} \quad \tan(2x) = \tan(\pi) = 0 \] 2. This gives us the form \(\infty^0\). We rewrite: \[ y = (\tan x)^{\tan 2x} \implies \ln y = \tan 2x \cdot \ln(\tan x) \] 3. As \(x \to \frac{\pi}{2}\), \(\tan 2x \to 0\) and \(\ln(\tan x) \to \infty\). We need to analyze: \[ \lim_{x \to \frac{\pi}{2}} \tan 2x \cdot \ln(\tan x) \] 4. Using L'Hôpital's Rule, we find: \[ \lim_{x \to \frac{\pi}{2}} \tan 2x \cdot \ln(\tan x) = 1 \] 5. Therefore, \[ \lim_{x \to \frac{\pi}{2}} (\tan x)^{\tan 2x} = e^{0} = 1. \] This corresponds to option **(s)**. ### Step 4: Evaluate Limit D **Limit D:** \[ \lim_{x \to \frac{\pi}{4}} \tan 2x \tan\left(\frac{\pi}{4} - x\right) \] 1. Substitute \(x = \frac{\pi}{4}\): \[ \tan 2\left(\frac{\pi}{4}\right) = \tan \frac{\pi}{2} \text{ (undefined)} \] 2. Rewrite: \[ \tan 2x = \frac{2\tan x}{1 - \tan^2 x} \quad \text{and} \quad \tan\left(\frac{\pi}{4} - x\right) = \frac{1 - \tan x}{1 + \tan x} \] 3. As \(x \to \frac{\pi}{4}\), both terms approach \(1\). 4. Therefore, \[ \lim_{x \to \frac{\pi}{4}} \tan 2x \tan\left(\frac{\pi}{4} - x\right) = 1 \cdot 1 = 1. \] This corresponds to option **(p)**. ### Final Matching - (A) → (q) - (B) → (r) - (C) → (s) - (D) → (p)
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