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[[Calculus]] provides an elegant way to determine the volume of this solid.  First, find where the curves intersect in order to ascertain the end-point of the integration.  The boundaries intersect where
 
[[Calculus]] provides an elegant way to determine the volume of this solid.  First, find where the curves intersect in order to ascertain the end-point of the integration.  The boundaries intersect where
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<math>y = \sqrt 2 = (\sec{x})(\tan{x})</math>
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:<math>y = \sqrt 2 = (\sec{x})(\tan{x})</math>
    
or  
 
or  
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<math>\sqrt 2 = \frac{\sin{x}}{\cos^2{x}}</math>
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:<math>\sqrt 2 = \frac{\sin{x}}{\cos^2{x}}</math>
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This is best solved by trial-and-error.  Since <math>\sin{\frac{\pi}{4}} = \cos{\frac{\pi}{4}}=\frac{\sqrt 2}{2}</math>, that is the solution.
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This is best solved by trial-and-error.  Since  
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The [[integral]] to find the volume of the solid must therefore be taken from ''x=0'' on one side to <math>x=\frac{\pi}{4}</math> on the other side.
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:<math>\sin{\frac{\pi}{4}} = \cos{\frac{\pi}{4}}=\frac{\sqrt 2}{2}</math>,
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that is the solution.  The [[integral]] to find the volume of the solid must therefore be taken from ''x=0'' on one side to:
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:<math>x=\frac{\pi}{4}</math>  
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on the other side.
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We are not ready to find the volume.  Note first that:
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:<math> dV = {\pi}r^2dx</math>
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and thus
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:<math>V = \int_0^\frac{\pi}{4} {\pi}r^2\,dx</math>
    
[[category:mathematics]]
 
[[category:mathematics]]
 
[[category:calculus]]
 
[[category:calculus]]
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