document.write( "Question 900982: find all possible pairs (a,b) of integers such that a^3=5b^3 \n" ); document.write( "

Algebra.Com's Answer #546365 by Edwin McCravy(20055) $\"\"$ $\"About$

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document.write( "(0,0) is a solution\r\n" );
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document.write( "Assume, for contradiction, that there are other solutions:\r\n" );
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document.write( "If (a,b) is a solution then (-a,-b) ia also a solution.\r\n" );
document.write( "So we only need consider that a and b are positive integers.\r\n" );
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document.write( " is a rational number which is the cube root of 5.\r\n" );
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document.write( "But the cube root of 5 is irrational.\r\n" );
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document.write( "Thus we have reached a contradiction.\r\n" );
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document.write( "Thus (0,0) is the only solution.\r\n" );
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document.write( "Edwin

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