Changes

Jump to navigation Jump to search
460 bytes added ,  05:36, December 16, 2007
improved
Line 3: Line 3:  
== Example ==
 
== Example ==
   −
Consider the region in the first quadrant that has an upper bound of <math>y = \sqrt 2</math> and a lower bound of <big><math>y = (\sec{x})(\tan{x})</math></big>, and on the left side by the ''y-axis''.  Find the volume of the solid formed by rotating the region about the line <math>y = \sqrt 2</math>.
+
Consider the region in the first quadrant that has an upper bound of <math>y = \sqrt 2</math> and a lower bound of <big><math>y = (\sec{x})(\tan{x})</math></big>, and bounded on the left side by the ''y-axis''.  Find the volume of the solid formed by rotating the region about the line <math>y = \sqrt 2</math>.
 +
 
 +
[[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
 +
 
 +
<math>y = \sqrt 2 = (\sec{x})(\tan{x})</math>
 +
 
 +
or
 +
 
 +
<math>\sqrt 2 = \frac{\sin{x}}{\cos^2{x}}</math>
 +
 
 +
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.
 +
 
 
[[category:mathematics]]
 
[[category:mathematics]]
 
[[category:calculus]]
 
[[category:calculus]]
Siteadmin, Bureaucrats, Check users, nsAm_Govt_101RO, nsAm_Govt_101RW, nsAm_Govt_101_ta, nsJudgesRO, nsJudgesRW, nsJudges_talkRO, nsJudges_talkRW, nsTeam2RO, nsTeam2RW, nsTeam2_talkRO, nsTeam2_talkRW, oversight, Administrators
125,789

edits

Navigation menu