document.write( "Question 717838: please help me solve this problem.\r
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Algebra.Com's Answer #440582 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "That area in the first quadrant looks like this:\r\n" );
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document.write( "and when it's rotated about the y-axis its cross section will look\r\n" );
document.write( "like this:\r\n" );
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document.write( "We will use the cylindrical shell method:\r\n" );
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document.write( "The volume of a cylindrical shell is:\r\n" );
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document.write( "(its circumference) times (its height) times (its thickness).\r\n" );
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document.write( "Its circumference is 2πr and its thickness is dx.  Its radius, r, is the x\r\n" );
document.write( "value of the point (x,y) which is just x. Its height, h, is just the y\r\n" );
document.write( "value of the point(x,y) which is just y, (which we will replace by x²-x³):  \r\n" );
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document.write( "V = \r\n" );
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document.write( "   \r\n" );
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document.write( "Edwin

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