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Let f(x)=min{sin^(-1)x,cos^(-1) x, (pi)/...

Let `f(x)=min{sin^(-1)x,cos^(-1) x, (pi)/6},x in [0,1]`. If area bounded by `y=f(x)` and X-axis, between the lines `x=0` and `x=1 is (a)/(b(sqrt(3)+1))`. Then , (a-b) is `"......."`.

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To solve the problem, we need to find the area bounded by the function \( f(x) = \min\{\sin^{-1} x, \cos^{-1} x, \frac{\pi}{6}\} \) over the interval \([0, 1]\). We will break this down step by step. ### Step 1: Identify the functions We have three functions to consider: 1. \( y = \sin^{-1} x \) 2. \( y = \cos^{-1} x \) 3. \( y = \frac{\pi}{6} \) ### Step 2: Determine the intersection points We need to find the points where these functions intersect within the interval \([0, 1]\). 1. **Intersection of \( \sin^{-1} x \) and \( \frac{\pi}{6} \)**: \[ \sin^{-1} x = \frac{\pi}{6} \implies x = \sin\left(\frac{\pi}{6}\right) = \frac{1}{2} \] 2. **Intersection of \( \cos^{-1} x \) and \( \frac{\pi}{6} \)**: \[ \cos^{-1} x = \frac{\pi}{6} \implies x = \cos\left(\frac{\pi}{6}\right) = \frac{\sqrt{3}}{2} \] ### Step 3: Define the function \( f(x) \) From the intersections, we can define \( f(x) \) in segments: - For \( x \in [0, \frac{1}{2}] \), \( f(x) = \sin^{-1} x \) - For \( x \in [\frac{1}{2}, \frac{\sqrt{3}}{2}] \), \( f(x) = \frac{\pi}{6} \) - For \( x \in [\frac{\sqrt{3}}{2}, 1] \), \( f(x) = \cos^{-1} x \) ### Step 4: Calculate the area under \( f(x) \) The area \( A \) can be calculated using definite integrals: \[ A = \int_0^{\frac{1}{2}} \sin^{-1} x \, dx + \int_{\frac{1}{2}}^{\frac{\sqrt{3}}{2}} \frac{\pi}{6} \, dx + \int_{\frac{\sqrt{3}}{2}}^1 \cos^{-1} x \, dx \] ### Step 5: Evaluate each integral 1. **First integral**: \[ \int \sin^{-1} x \, dx = x \sin^{-1} x + \sqrt{1 - x^2} + C \] Evaluating from \( 0 \) to \( \frac{1}{2} \): \[ \left[ x \sin^{-1} x + \sqrt{1 - x^2} \right]_0^{\frac{1}{2}} = \left[ \frac{1}{2} \cdot \frac{\pi}{6} + \sqrt{1 - \left(\frac{1}{2}\right)^2} \right] - \left[ 0 + 1 \right] \] \[ = \frac{\pi}{12} + \frac{\sqrt{3}}{2} - 1 \] 2. **Second integral**: \[ \int_{\frac{1}{2}}^{\frac{\sqrt{3}}{2}} \frac{\pi}{6} \, dx = \frac{\pi}{6} \left( \frac{\sqrt{3}}{2} - \frac{1}{2} \right) = \frac{\pi}{6} \cdot \frac{\sqrt{3} - 1}{2} = \frac{\pi(\sqrt{3} - 1)}{12} \] 3. **Third integral**: \[ \int \cos^{-1} x \, dx = x \cos^{-1} x + \sqrt{1 - x^2} + C \] Evaluating from \( \frac{\sqrt{3}}{2} \) to \( 1 \): \[ \left[ x \cos^{-1} x + \sqrt{1 - x^2} \right]_{\frac{\sqrt{3}}{2}}^1 = \left[ 1 \cdot 0 + 0 \right] - \left[ \frac{\sqrt{3}}{2} \cdot \frac{\pi}{6} + \frac{1}{2} \right] \] \[ = 0 - \left[ \frac{\sqrt{3}\pi}{12} + \frac{1}{2} \right] = -\frac{\sqrt{3}\pi}{12} - \frac{1}{2} \] ### Step 6: Combine the areas Now, we can combine all the areas: \[ A = \left( \frac{\pi}{12} + \frac{\sqrt{3}}{2} - 1 \right) + \frac{\pi(\sqrt{3} - 1)}{12} - \left( \frac{\sqrt{3}\pi}{12} + \frac{1}{2} \right) \] ### Step 7: Simplify the expression Combine like terms: \[ A = \frac{\pi}{12} + \frac{\sqrt{3}}{2} - 1 + \frac{\pi\sqrt{3}}{12} - \frac{\pi}{12} - \frac{\sqrt{3}\pi}{12} - \frac{1}{2} \] \[ = \frac{\sqrt{3}}{2} - 1 - \frac{1}{2} = \frac{\sqrt{3}}{2} - \frac{3}{2} = \frac{\sqrt{3} - 3}{2} \] ### Step 8: Express in the required form We need to express \( A \) in the form \( \frac{a}{b(\sqrt{3}+1)} \): \[ \frac{\sqrt{3} - 3}{2} = \frac{(\sqrt{3} - 3)(\sqrt{3} + 1)}{2(\sqrt{3} + 1)} = \frac{3 - 3\sqrt{3} - 3}{2(\sqrt{3} + 1)} = \frac{-3\sqrt{3}}{2(\sqrt{3} + 1)} \] From this, we can identify \( a = -3 \) and \( b = 2 \). ### Step 9: Find \( a - b \) \[ a - b = -3 - 2 = -5 \] ### Final Answer Thus, the final answer is: \[ \boxed{-5} \]
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