document.write( "Question 1162750: If the positive integers a and b satisfy √a − √b = √11, what is the maximum value of a/b? \n" ); document.write( "
Algebra.Com's Answer #786585 by greenestamps(13215)\"\" \"About 
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\n" ); document.write( "The following original response left out important parts of the solution -- though the final answer to the question was correct. See further down for the corrected/expanded response.

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\n" ); document.write( "If a and b are integers and \"sqrt%28a%29-sqrt%28b%29+=+sqrt%2811%29\", then for some positive integer value of n,

\n" ); document.write( "\"a=%28n%2B1%29%5E2\" and \"b+=+n%5E2\"

\n" ); document.write( "Then \"a%2Fb+=+%28n%2B1%29%5E2%2Fn%5E2+=+%28%28n%2B1%29%2Fn%29%5E2\"

\n" ); document.write( "For positive integer values of n, the maximum value of a/b is clearly when n=1 and a/b = (2/1)^2 = 4.

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\n" ); document.write( "Corrected response....

\n" ); document.write( "If a and b are integers and \"sqrt%28a%29-sqrt%28b%29+=+sqrt%2811%29\", then for some positive integer value of n,

\n" ); document.write( "\"a=%2811%28n%2B1%29%5E2%29\" and \"b+=+11%28n%5E2%29\"

\n" ); document.write( "With those values of a and b,
\n" ); document.write( "\"sqrt%28a%29+=+%28n%2B1%29%2Asqrt%2811%29\"
\n" ); document.write( "\"sqrt%28b%29+=+%28n%29%2Asqrt%2811%29\"
\n" ); document.write( "\"sqrt%28a%29-sqrt%28b%29+=+%28n%2B1%29%2Asqrt%2811%29-%28n%29%2Asqrt%2811%29+=+sqrt%2811%29\"

\n" ); document.write( "Then \"a%2Fb+=+%28n%2B1%29%5E2%2Fn%5E2+=+%28%28n%2B1%29%2Fn%29%5E2+=+%281%2B1%2Fn%29%5E2\"

\n" ); document.write( "For positive integer values of n, the maximum value of a/b is clearly when n=1 and a/b = (2/1)^2 = 4.

\n" ); document.write( "CHECK....

\n" ); document.write( "n=1: a = 11(2^2) = 44; b = 11(1^2) = 11; \"sqrt%28a%29-sqrt%28b%29+=+2%2Asqrt%2811%29-1%2Asqrt%2811%29+=+sqrt%2811%29\"; a/b = 44/11 = 4

\n" ); document.write( "n=2: a = 11(3^2) = 99; b = 11(2^2) = 44; \"sqrt%28a%29-sqrt%28b%29+=+3%2Asqrt%2811%29-2%2Asqrt%2811%29+=+sqrt%2811%29\"; a/b = 99/44 = 9/4

\n" ); document.write( "n=3: a = 11(4^2) = 176; b = 11(3^2) = 99; \"sqrt%28a%29-sqrt%28b%29+=+4%2Asqrt%2811%29-3%2Asqrt%2811%29+=+sqrt%2811%29\"; a/b = 176/99 = 16/9


\n" ); document.write( "Clearly for larger values of n the ratio a/b will continue to get smaller....

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