document.write( "Question 1176683: Integration :Find the area bounded by y=xe^-x, y=0, and x=2\r
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Algebra.Com's Answer #803877 by math_helper(2461) $\"\"$ $\"About$

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document.write( "The first step is to note that the lower limit of integration will be x=0.  This is because y=0 is one of the boundaries and y is negative for x<0.  So we will have limits of integration of x=0 and x=2.\r
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document.write( "Use integration by parts:\r
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document.write( "   Let          and    
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document.write( "giving us    and     \r
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document.write( "Recall integration by parts:
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document.write( " =  - \r
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document.write( " =  - 
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document.write( "                        =  - 
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document.write( "                        = \r
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document.write( "Evaluate this expression at x=2:  -0.4060  (approx)
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document.write( "                     and at x=0:   -1\r
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document.write( "Subtract the bottom from the top:  -0.4060-(-1) = 0.5940 sq units. (to 4 decimal places)\r
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