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The value of int(0)^(1)(tan^(-1)x)/(cot^...

The value of `int_(0)^(1)(tan^(-1)x)/(cot^(-1)(1-x+x^(2))dx` is____.

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To solve the integral \[ I = \int_{0}^{1} \frac{\tan^{-1} x}{\cot^{-1}(1 - x + x^2)} \, dx, \] we will follow these steps: ### Step 1: Simplify the denominator We know that \[ \cot^{-1} y = \frac{\pi}{2} - \tan^{-1} y. \] Thus, we can rewrite the denominator: \[ \cot^{-1}(1 - x + x^2) = \frac{\pi}{2} - \tan^{-1}(1 - x + x^2). \] ### Step 2: Rewrite the integral Substituting this into the integral gives: \[ I = \int_{0}^{1} \frac{\tan^{-1} x}{\frac{\pi}{2} - \tan^{-1}(1 - x + x^2)} \, dx. \] ### Step 3: Use the property of definite integrals We can use the property of definite integrals: \[ \int_{a}^{b} f(x) \, dx = \int_{a}^{b} f(a + b - x) \, dx. \] In our case, \(a = 0\) and \(b = 1\), so we have: \[ I = \int_{0}^{1} \frac{\tan^{-1}(1 - x)}{\cot^{-1}(1 - (1 - x) + (1 - x)^2)} \, dx. \] ### Step 4: Simplify the new integral Now, simplify the new integral: \[ 1 - (1 - x) + (1 - x)^2 = 1 - 1 + x + (1 - 2x + x^2) = x^2 - x + 1. \] Thus, we have: \[ I = \int_{0}^{1} \frac{\tan^{-1}(1 - x)}{\cot^{-1}(x^2 - x + 1)} \, dx. \] ### Step 5: Combine the two integrals Now we have two expressions for \(I\): 1. \( I = \int_{0}^{1} \frac{\tan^{-1} x}{\cot^{-1}(1 - x + x^2)} \, dx \) 2. \( I = \int_{0}^{1} \frac{\tan^{-1}(1 - x)}{\cot^{-1}(x^2 - x + 1)} \, dx \) Adding these two equations gives: \[ 2I = \int_{0}^{1} \left( \frac{\tan^{-1} x + \tan^{-1}(1 - x)}{\cot^{-1}(1 - x + x^2)} \right) \, dx. \] ### Step 6: Use the identity for arctangent Using the identity: \[ \tan^{-1} x + \tan^{-1}(1 - x) = \frac{\pi}{4}, \] we can simplify: \[ 2I = \int_{0}^{1} \frac{\frac{\pi}{4}}{\cot^{-1}(1 - x + x^2)} \, dx. \] ### Step 7: Evaluate the integral Now, since \(\cot^{-1}(1 - x + x^2)\) is a continuous function over the interval \([0, 1]\), we can evaluate: \[ 2I = \frac{\pi}{4} \int_{0}^{1} \frac{1}{\cot^{-1}(1 - x + x^2)} \, dx. \] ### Step 8: Solve for \(I\) Finally, we can solve for \(I\): \[ I = \frac{1}{2} \int_{0}^{1} 1 \, dx = \frac{1}{2} \cdot (1 - 0) = \frac{1}{2}. \] Thus, the value of the integral is \[ \boxed{\frac{1}{2}}. \]

To solve the integral \[ I = \int_{0}^{1} \frac{\tan^{-1} x}{\cot^{-1}(1 - x + x^2)} \, dx, \] we will follow these steps: ...
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Knowledge Check

  • int_(0)^(1)x tan^(-1)x dx=

    A
    `(pi)/(4)-(log 2)`
    B
    `(pi)/(4)-(1)/(2)`
    C
    `(pi)/(4)-1`
    D
    `(pi)/(4)+(log 2)`
  • If int_(0)^(1) tan^(-1) x dx = p , then the value of int_(0)^(1) tan^(-1)((1-x)/(1 +x)) dx is

    A
    `(pi)/(4) + p`
    B
    `(pi)/(4) - p`
    C
    `1 + p`
    D
    `1 - p`
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