document.write( "Question 864949: HI,
\n" ); document.write( "A wire of length 40 inches is to be cut into two pieces, each of which will be used to form a circle. Suppose we will be charged $2 for each square inch of area enclosed by the first circle, and $1 for each inch in the second circle's circumference. Find the lengths of the two pieces of wire which will
\n" ); document.write( "minimize the total cost.
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Algebra.Com's Answer #521410 by Alan3354(69443)\"\" \"About 
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A wire of length 40 inches is to be cut into two pieces, each of which will be used to form a circle. Suppose we will be charged $2 for each square inch of area enclosed by the first circle, and $1 for each inch in the second circle's circumference. Find the lengths of the two pieces of wire which will
\n" ); document.write( "minimize the total cost.
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\n" ); document.write( "C = length of wire in the 1st circle ($2 per sq inch)
\n" ); document.write( "\"C+=+2pi%2Ar\"
\n" ); document.write( " --> \"r+=+C%2F2pi\"
\n" ); document.write( "\"Area+=+pi%2Ar%5E2+=+pi%2A%28C%5E2%2F4pi%5E2%29+=+C%5E2%2F4pi\"
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\n" ); document.write( "--> $1/inch of 40 - C for the 2nd circle
\n" ); document.write( "----
\n" ); document.write( "Price = \"2%2AC%5E2%2F4pi+%2B+40+-+C\"
\n" ); document.write( "P(C) = \"C%5E2%2F2pi+-+C+%2B+40\"
\n" ); document.write( "P'(C) = \"C%2Fpi+-+1+=+0\"
\n" ); document.write( "C = pi inches for the 1st circle
\n" ); document.write( "40 - pi inches for the 2nd
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