document.write( "Question 1142727: **Solve using calculus optimization**\r
\n" ); document.write( "\n" ); document.write( "Find the point on the curve \"+y=x%5E2+\" that is closest to the point (18, 0).
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Algebra.Com's Answer #763457 by Alan3354(69443)\"\" \"About 
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Find the point on the curve \"+y=x%5E2+\" that is closest to the point (18, 0).
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\n" ); document.write( "The points on the curve are (x,x^2)
\n" ); document.write( "The distance d(x) to (18,0) is \"sqrt%28%28x-18%29%5E2+%2B+%28x%5E2-0%29%5E2%29\"
\n" ); document.write( "d(x) = \"sqrt%28x%5E4+%2B+x%5E2+-+36x+%2B324%29\"
\n" ); document.write( "d'(x) = (1/2)*(4x^3 + 2x - 36)/sqrt(...) = 0
\n" ); document.write( "2x^3 + x - 18 = 0
\n" ); document.write( "x = 2
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\n" ); document.write( "The point is (2,4)
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\n" ); document.write( "The distance is sqrt(16^2 + 4^2) = 4sqrt(17) units.
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