document.write( "Question 1055178: What is the minimum distance between the 2 parabolas:
\n" ); document.write( "y = x^2+4 and x = y^2 ?
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Algebra.Com's Answer #670381 by Fombitz(32388)\"\" \"About 
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OK, assume that the shortest distance line segment intersects the first curve at (\"a\",\"a%5E2%2B4\") and intersects the second curve at (\"b%5E2\",\"b\").
\n" ); document.write( "The slope of the tangent line of the first curve at point \"a\" would be \"2a\" since \"dy%2Fdx=2x\".
\n" ); document.write( "The slope of the tangent line of the second curve at point \"b\" would be \"1%2F%282b%29\" since \"dy%2Fdx=1%2F%282%2Asqrt%28x%29%29\".
\n" ); document.write( "The slopes are equivalent which leads to the first equation,
\n" ); document.write( "\"2a=1%2F%282b%29\"
\n" ); document.write( "\"4ab=1\"
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\n" ); document.write( "Now use the distance formula (actually use the distance squared to eliminate the square root) with the two points of intersection,
\n" ); document.write( "\"D%5E2=%28a-b%5E2%29%5E2%2B%28a%5E2%2B4-b%29%5E2\"
\n" ); document.write( "From the previous equation,
\n" ); document.write( "\"a=1%2F%284b%29\"
\n" ); document.write( "Substitute,
\n" ); document.write( "\"D%5E2=%281%2F%284b%29-b%5E2%29%5E2%2B%281%2F%2816b%29%2B4-b%29%5E2\"
\n" ); document.write( "Graphing and finding the minimum,
\n" ); document.write( "\"b=1.188\"
\n" ); document.write( "So then,
\n" ); document.write( "\"a=1%2F%284b%29\"
\n" ); document.write( "\"a=0.210438\"
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\n" ); document.write( "So then the points are (\"0.210\",\"4.044\") and (\"1.188\",\"1.411\")
\n" ); document.write( "Using the distance formula,
\n" ); document.write( "\"D%5Bmin%5D=3.098\"
\n" ); document.write( "You could also have just used the graphed value when we minimized the distance squared,
\n" ); document.write( "\"D%5Bmin%5D%5E2=9.601\"
\n" ); document.write( "\"D%5Bmin%5D=3.098\"
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