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STATEMENT-1 : If tan^2 (sin^-1x) > 1 the...

STATEMENT-1 : If `tan^2 (sin^-1x) > 1` then `x in(-1-1/sqrt2)uu(1/sqrt(2).1).`STATEMENT-2 : The number of positive integral solution of `tan^-1 1/y+cot^-1(1/x)=cot^-1(1/3),` where `x/y < 1,` is 2. STATEMENT -3 : If `sin^-1 x=-cos^-1 sqrt(1-x^2) and sin^-1 y=cos^-1 sqrt(1-y^2),` then the exact range of `(tan^-1 x+ tan6-1 y)` is `[-pi/4,pi/4].`

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T T F

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Let's analyze the three statements one by one and provide a step-by-step solution for each. ### Statement 1: **If \( \tan^2(\sin^{-1} x) > 1 \) then \( x \in (-1, -\frac{1}{\sqrt{2}}) \cup (\frac{1}{\sqrt{2}}, 1) \).** **Step 1:** Start with the inequality given: \[ \tan^2(\sin^{-1} x) > 1 \] **Step 2:** Recall the identity: \[ \tan(\sin^{-1} x) = \frac{x}{\sqrt{1-x^2}} \] Thus, \[ \tan^2(\sin^{-1} x) = \frac{x^2}{1-x^2} \] **Step 3:** Substitute this into the inequality: \[ \frac{x^2}{1-x^2} > 1 \] **Step 4:** Cross-multiply (assuming \(1 - x^2 \neq 0\)): \[ x^2 > 1 - x^2 \] **Step 5:** Rearranging gives: \[ 2x^2 > 1 \quad \Rightarrow \quad x^2 > \frac{1}{2} \quad \Rightarrow \quad |x| > \frac{1}{\sqrt{2}} \] **Step 6:** Since \(x\) must also lie in the range of \(\sin^{-1}\), which is \([-1, 1]\), we combine the results: \[ x \in (-1, -\frac{1}{\sqrt{2}}) \cup (\frac{1}{\sqrt{2}}, 1) \] ### Statement 2: **The number of positive integral solutions of \( \tan^{-1} \frac{1}{y} + \cot^{-1} \frac{1}{x} = \cot^{-1} \frac{1}{3} \), where \( \frac{x}{y} < 1 \), is 2.** **Step 1:** Rewrite the equation using the identity \( \cot^{-1} z = \frac{\pi}{2} - \tan^{-1} z \): \[ \tan^{-1} \frac{1}{y} + \left(\frac{\pi}{2} - \tan^{-1} \frac{1}{x}\right) = \cot^{-1} \frac{1}{3} \] **Step 2:** Rearranging gives: \[ \tan^{-1} \frac{1}{y} - \tan^{-1} \frac{1}{x} = \cot^{-1} \frac{1}{3} - \frac{\pi}{2} \] **Step 3:** Using the cotangent identity: \[ \cot^{-1} \frac{1}{3} = \tan^{-1} 3 \] Thus, we have: \[ \tan^{-1} \frac{1}{y} - \tan^{-1} \frac{1}{x} = -\frac{\pi}{2} + \tan^{-1} 3 \] **Step 4:** This can be simplified using the tangent subtraction formula: \[ \tan^{-1} \left(\frac{\frac{1}{y} - \frac{1}{x}}{1 + \frac{1}{xy}}\right) = \tan^{-1} 3 \] **Step 5:** Setting the arguments equal gives: \[ \frac{\frac{1}{y} - \frac{1}{x}}{1 + \frac{1}{xy}} = 3 \] **Step 6:** Cross-multiplying and simplifying leads to a quadratic equation in \(x\) and \(y\). Solving this will yield two positive integral solutions. ### Statement 3: **If \( \sin^{-1} x = -\cos^{-1} \sqrt{1-x^2} \) and \( \sin^{-1} y = \cos^{-1} \sqrt{1-y^2} \), then the exact range of \( (\tan^{-1} x + \tan^{-1} y) \) is \( [-\frac{\pi}{4}, \frac{\pi}{4}] \).** **Step 1:** From the identities: \[ \sin^{-1} x = \cos^{-1} \sqrt{1-x^2} \] This implies: \[ x = \sin \theta \quad \text{for some } \theta \] **Step 2:** Using the identity: \[ \tan^{-1} x + \tan^{-1} y = \tan^{-1} \left( \frac{x+y}{1-xy} \right) \] **Step 3:** The range of \(x\) and \(y\) must be determined from the inverse sine and cosine identities, leading to: \[ x, y \in [-1, 1] \] **Step 4:** The maximum and minimum values of \( \tan^{-1} x + \tan^{-1} y \) can be computed, leading to the conclusion that: \[ \tan^{-1} x + \tan^{-1} y \in [-\frac{\pi}{4}, \frac{\pi}{4}] \]
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