document.write( "Question 954959: A rectangle has one vertex in quadrant 1 on the graph of y=16-x^2, another at the origin, one on the positive x-axis, and one on the positive y-axis.\r
\n" ); document.write( "\n" ); document.write( "Express the area A of the rectangle as a function of x.
\n" ); document.write( "My answer: A(x)= 16x-x^3\r
\n" ); document.write( "\n" ); document.write( "Find the largest area A that can be enclosed by the rectangle?
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Algebra.Com's Answer #583340 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
The area of the rectangle would be,
\n" ); document.write( "\"A=x%2Ay\"
\n" ); document.write( "\"A=x%2816-x%5E2%29\"
\n" ); document.write( "\"A=16x-x%5E3\"
\n" ); document.write( "So far you are correct.
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\n" ); document.write( "To find the maximum, take the derivative with respect to x and solve when the derivative equals zero.
\n" ); document.write( "\"dA%2Fdx=16-3x%5E2=0\"
\n" ); document.write( "\"3x%5E2=16\"
\n" ); document.write( "\"x%5E2=16%2F3\"
\n" ); document.write( "\"x=4%2Fsqrt%283%29\"
\n" ); document.write( "\"x=%284%2F3%29sqrt%283%29\"
\n" ); document.write( "So then,
\n" ); document.write( "\"A%5Bmax%5D=16%284%2F3%29sqrt%283%29-%2816%2F3%29%284%2F3%29sqrt%283%29\"
\n" ); document.write( "\"A%5Bmax%5D=%28128%2F9%29sqrt%283%29\"\r
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