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If sin^(-1)x+sin^(-1)y=(2pi)/3 and cos^(...

If `sin^(-1)x+sin^(-1)y=(2pi)/3` and `cos^(-1)x-cos^(-1)y=-pi/3` then the number of values of `(x,y)` is

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To solve the problem step by step, we start with the given equations: 1. **Given Equations**: \[ \sin^{-1} x + \sin^{-1} y = \frac{2\pi}{3} \quad \text{(1)} \] \[ \cos^{-1} x - \cos^{-1} y = -\frac{\pi}{3} \quad \text{(2)} \] 2. **Using the Identity**: We know that: \[ \sin^{-1} x + \cos^{-1} x = \frac{\pi}{2} \] and \[ \sin^{-1} y + \cos^{-1} y = \frac{\pi}{2} \] 3. **Adding Equations (1) and (2)**: Adding the two equations gives: \[ \sin^{-1} x + \sin^{-1} y + \cos^{-1} x - \cos^{-1} y = \frac{2\pi}{3} - \frac{\pi}{3} \] Simplifying the right side: \[ \sin^{-1} x + \sin^{-1} y + \cos^{-1} x - \cos^{-1} y = \frac{\pi}{3} \] 4. **Substituting the Identities**: Substitute the identities into the equation: \[ \sin^{-1} x + \left(\frac{\pi}{2} - \sin^{-1} x\right) + \sin^{-1} y - \left(\frac{\pi}{2} - \sin^{-1} y\right) = \frac{\pi}{3} \] This simplifies to: \[ \sin^{-1} y - \sin^{-1} y + \frac{\pi}{2} - \frac{\pi}{2} = \frac{\pi}{3} \] This does not yield new information, so we will proceed differently. 5. **Rearranging Equation (2)**: Rearranging equation (2) gives: \[ \cos^{-1} x = \cos^{-1} y - \frac{\pi}{3} \] 6. **Using the Cosine Identity**: Taking cosine on both sides: \[ x = \cos\left(\cos^{-1} y - \frac{\pi}{3}\right) \] Using the cosine subtraction formula: \[ x = \cos(\cos^{-1} y)\cos\left(\frac{\pi}{3}\right) + \sin(\cos^{-1} y)\sin\left(\frac{\pi}{3}\right) \] Thus, \[ x = y \cdot \frac{1}{2} + \sqrt{1 - y^2} \cdot \frac{\sqrt{3}}{2} \] Simplifying gives: \[ x = \frac{y}{2} + \frac{\sqrt{3}}{2}\sqrt{1 - y^2} \] 7. **Substituting into Equation (1)**: Substitute \(x\) back into equation (1): \[ \sin^{-1}\left(\frac{y}{2} + \frac{\sqrt{3}}{2}\sqrt{1 - y^2}\right) + \sin^{-1}(y) = \frac{2\pi}{3} \] 8. **Finding Values**: Solving this equation will yield the values of \(y\) and subsequently \(x\). However, we can check the possible values of \(y\) within the range \([-1, 1]\). 9. **Conclusion**: After solving, we find that: \[ y = \frac{1}{2} \quad \text{and} \quad x = 1 \] Thus, the only pair \((x, y)\) is \((1, \frac{1}{2})\). 10. **Final Answer**: The number of values of \((x, y)\) is **1**.

To solve the problem step by step, we start with the given equations: 1. **Given Equations**: \[ \sin^{-1} x + \sin^{-1} y = \frac{2\pi}{3} \quad \text{(1)} \] \[ \cos^{-1} x - \cos^{-1} y = -\frac{\pi}{3} \quad \text{(2)} ...
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