document.write( "Question 1103012: a. The equation r2 = 4cos2θ is of the form r^2 = a^2*cos2θ, so the graph is a lemniscate. What is the length of each loop?\r
\n" ); document.write( "\n" ); document.write( "b. At what values of θ do the endpoints of each loop occur?
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Algebra.Com's Answer #717736 by Fombitz(32388)\"\" \"About 
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For a lemniscate of the form,
\n" ); document.write( "\"r%5E2=a%5E2%2Acos%282%2Atheta%29\"
\n" ); document.write( "the arc length is,
\n" ); document.write( "\"S=%28a%2Fsqrt%282pi%29%29%2AGAMMA%281%2F4%29%5E2\" where \"GAMMA\" is the gamma function.
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\n" ); document.write( "\"GAMMA%281%2F2%29=sqrt%28pi%29\"
\n" ); document.write( "So,
\n" ); document.write( "\"s=%282%2Fsqrt%282pi%29%29pi\"
\n" ); document.write( "\"s=sqrt%282pi%29\"
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\n" ); document.write( "The maximum absolute value of the cosine is equal to 1 and occurs when the argument \"2%2Atheta=0\" and \"2%2Atheta=pi\". So then when,
\n" ); document.write( "\"theta=0\"
\n" ); document.write( "\"theta=%281%2F2%29pi\"
\n" ); document.write( "\"theta=pi\"
\n" ); document.write( "\"theta=%283%2F2%29pi\"
\n" ); document.write( "and equals zero when,
\n" ); document.write( "\"theta=%281%2F4%29pi\"
\n" ); document.write( "\"theta=%283%2F4%29pi\"
\n" ); document.write( "\"theta=%285%2F4%29pi\"
\n" ); document.write( "\"theta=%287%2F4%29pi\"
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