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If x in (0, 1), then find the value of t...

If `x in (0, 1)`, then find the value of `tan^(-1) ((1 -x^(2))/(2x)) + cos^(-1) ((1 -x^(2))/(1 + x^(2)))`

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To solve the problem, we need to find the value of \[ \tan^{-1} \left( \frac{1 - x^2}{2x} \right) + \cos^{-1} \left( \frac{1 - x^2}{1 + x^2} \right) \] for \( x \in (0, 1) \). ### Step 1: Rewrite the cosine inverse term We start by rewriting the cosine inverse term in a form that can be related to tangent. We know that \[ \cos^{-1}(y) = \tan^{-1}\left(\frac{\sqrt{1 - y^2}}{y}\right) \] for \( y = \frac{1 - x^2}{1 + x^2} \). ### Step 2: Calculate \( \sqrt{1 - y^2} \) First, we need to calculate \( 1 - y^2 \): \[ y^2 = \left(\frac{1 - x^2}{1 + x^2}\right)^2 = \frac{(1 - x^2)^2}{(1 + x^2)^2} \] Now, \[ 1 - y^2 = 1 - \frac{(1 - x^2)^2}{(1 + x^2)^2} = \frac{(1 + x^2)^2 - (1 - x^2)^2}{(1 + x^2)^2} \] Calculating the numerator: \[ (1 + x^2)^2 - (1 - x^2)^2 = (1 + 2x^2 + x^4) - (1 - 2x^2 + x^4) = 4x^2 \] Thus, \[ 1 - y^2 = \frac{4x^2}{(1 + x^2)^2} \] ### Step 3: Substitute back into the cosine inverse Now substituting back into the expression for cosine inverse: \[ \cos^{-1}\left(\frac{1 - x^2}{1 + x^2}\right) = \tan^{-1}\left(\frac{\sqrt{1 - y^2}}{y}\right) = \tan^{-1}\left(\frac{\sqrt{\frac{4x^2}{(1 + x^2)^2}}}{\frac{1 - x^2}{1 + x^2}}\right) \] This simplifies to: \[ \tan^{-1}\left(\frac{\frac{2x}{1 + x^2}}{\frac{1 - x^2}{1 + x^2}}\right) = \tan^{-1}\left(\frac{2x}{1 - x^2}\right) \] ### Step 4: Combine the terms Now we can combine the two terms: \[ \tan^{-1}\left(\frac{1 - x^2}{2x}\right) + \tan^{-1}\left(\frac{2x}{1 - x^2}\right) \] Using the formula for the sum of inverse tangents: \[ \tan^{-1}(a) + \tan^{-1}(b) = \tan^{-1}\left(\frac{a + b}{1 - ab}\right) \] where \( a = \frac{1 - x^2}{2x} \) and \( b = \frac{2x}{1 - x^2} \). ### Step 5: Calculate \( a + b \) and \( 1 - ab \) Calculating \( a + b \): \[ a + b = \frac{1 - x^2}{2x} + \frac{2x}{1 - x^2} = \frac{(1 - x^2)^2 + 4x^2}{2x(1 - x^2)} = \frac{1 - 2x^2 + x^4 + 4x^2}{2x(1 - x^2)} = \frac{1 + 2x^2 + x^4}{2x(1 - x^2)} \] Calculating \( ab \): \[ ab = \left(\frac{1 - x^2}{2x}\right) \left(\frac{2x}{1 - x^2}\right) = 1 \] Thus, \( 1 - ab = 0 \). ### Step 6: Conclusion Since \( 1 - ab = 0 \), the expression becomes undefined, which corresponds to \( \tan^{-1}(\infty) \), or \( \frac{\pi}{2} \). Therefore, the final result is: \[ \boxed{\frac{\pi}{2}} \]

To solve the problem, we need to find the value of \[ \tan^{-1} \left( \frac{1 - x^2}{2x} \right) + \cos^{-1} \left( \frac{1 - x^2}{1 + x^2} \right) \] for \( x \in (0, 1) \). ...
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