document.write( "Question 1137641: Find the unit digit of 64^401 \n" ); document.write( "
Algebra.Com's Answer #755481 by Edwin McCravy(20060)\"\" \"About 
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document.write( "The unit digit of an integer is the digit it ends in.\r\n" );
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document.write( "Odd powers of positive integers ending in 4 end in 4.\r\n" );
document.write( "Even powers of positive integers ending in 4 end in 6.\r\n" );
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document.write( "64 is an integer ending in 4 and the 401th power is an odd power,\r\n" );
document.write( "so 64^401 ends in 4.\r\n" );
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document.write( "Edwin
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