document.write( "Question 1003297: Find the midpoint riemann sum for f(x) = cos(2x) on the partition
\n" ); document.write( "P = {-pi/2,0,pi/3,pi/2} \r
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\n" ); document.write( "\n" ); document.write( "Please show how this is done
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Algebra.Com's Answer #620266 by richard1234(7193)\"\" \"About 
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First sketch f(x) on the xy-plane and label the points (-pi/2, 0), (0,0), (0, pi/3), and (0,pi/2) (corresponding to the points in P).\r
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\n" ); document.write( "\n" ); document.write( "To approximate the integral using the midpoint Riemann sum, for each \"interval\" bounded by consecutive points in P, take the midpoint and evaluate f at that x-value. This becomes your \"height\" of the rectangle. Multiply by the width of the interval.\r
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\n" ); document.write( "\n" ); document.write( "For example, for the interval bounded by -pi/2, 0, we would want to take -pi/4 and compute f(-pi/4). Then we multiply f(-pi/4) by pi/2 (the width of the interval). Repeat for the other intervals and add.
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