document.write( "Question 199429: A length of wire is cut into two pieces, one of which is bent to form a circle, the other a square. How should the wire be cut if the area enclosed by the two curves is to be a minimum? \n" ); document.write( "
Algebra.Com's Answer #149879 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
Let the total length of the wire = \"1\"
\n" ); document.write( "Let the length of a side of the square = \"x\"
\n" ); document.write( "The area of the square will be \"x%5E2\"
\n" ); document.write( "The perimeter of the square will be \"4x\"
\n" ); document.write( "The perimeter of the circle will be \"1+-+4x\"
\n" ); document.write( "Let the perimeter of the circle = \"P\"
\n" ); document.write( "Let the radius = \"r\"
\n" ); document.write( "\"P+=+2%2Api%2Ar\"
\n" ); document.write( "\"2%2Api%2Ar+=+1+-+4x\"
\n" ); document.write( "\"r+=+%281+-+4x%29%2F%282%2Api%29\"
\n" ); document.write( "Let area of circle = \"A\"
\n" ); document.write( "\"A+=+pi%2Ar%5E2\"
\n" ); document.write( "\"A+=+pi%2A%281+-+4x%29%5E2%2F%282%2Api%29%5E2\"
\n" ); document.write( "\"A+=+%28pi%2A%281+-+8x+%2B+16x%5E2%29%29%2F%284%2Api%5E2%29\"
\n" ); document.write( "\"A+=+%2816x%5E2+-+8x+%2B+1%29%2F%284%2Api%29\"
\n" ); document.write( "The total area is:
\n" ); document.write( "\"A+=+%2816x%5E2+-+8x+%2B+1%29%2F%284%2Api%29+%2B+x%5E2\"
\n" ); document.write( "Multiply both sides by \"4%2Api\"
\n" ); document.write( "\"4%2Api%2AA+=+%2816+%2B+4%2Api%29%2Ax%5E2+-+8x+%2B+1\"
\n" ); document.write( "If I make \"4%2Api%2AA\" a minimum, \"A\" will be a minimum
\n" ); document.write( "With a parabola, the minimum occurs at \"x%5Bmin%5D+=+-b%2F%282a%29\"
\n" ); document.write( "\"b=+-8\"
\n" ); document.write( "\"a+=+16+%2B+4%2Api\"
\n" ); document.write( "\"x%5Bmin%5D+=+-%28-8%29%2F%282%2A%2816+%2B+4%2Api%29%29\"
\n" ); document.write( "\"x%5Bmin%5D+=+8%2F%2832+%2B+8%2Api%29\"
\n" ); document.write( "\"x%5Bmin%5D+=+1%2F%284+%2B+pi%29\"
\n" ); document.write( "The perimeter of the square is:
\n" ); document.write( "\"4x+=+4%2F%284+%2B+pi%29\"
\n" ); document.write( "The perimeter of the circle is:
\n" ); document.write( "\"1+-+%284%2F%284+%2B+pi%29%29+=+%284+%2B+pi%29%2F%284+%2B+pi%29+-+%284%2F%284+%2B+pi%29%29\"
\n" ); document.write( "\"%284+%2B+pi+-+4%29+%2F+%284+%2B+pi%29\"
\n" ); document.write( "\"pi%2F%284+%2B+pi%29\"
\n" ); document.write( "The cut should be made so the lengths of
\n" ); document.write( "the two wires are \"4%2F%284+%2B+pi%29\" and \"pi%2F%284+%2B+pi%29\"
\n" ); document.write( "Hope I didn't make a mistake- this is the way to do it, though
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