document.write( "Question 179657: Based on my previous questions and the answer provided:
\n" ); document.write( "``Hello I have a question regarding the easiest way to find the positive divisors of a number. I know there is a way to find them in a quick way instead of going through every number. For example I have this number 372. and even though I got the answer, it willtake me for ever to come up with 1,2,3,4,6,12,32,62,93,124,186,372. Please can you explain me how can I find the positive divisors more effectively? \"\r
\n" ); document.write( "\n" ); document.write( "Answer: \"You just have to obtain the prime factor decomposition of the number and then to combine those factors in all possible forms.
\n" ); document.write( "If they only ask you only by the NUMBER of divisors, that's a lot easier. It's only a problem of counting. For example:
\n" ); document.write( "756 = (3^3) * (2^2) * 7
\n" ); document.write( "Any factor you may have will be a combination (product) of these factors. You have available 3 \"3\"s, 2 \"2\"s and 1 \"7\", so
\n" ); document.write( "# of ways factor \"3\" may appear = 3 + 1 = 4 (3^0, 3^1, 3^2, 3^3)
\n" ); document.write( "# of ways factor \"2\" may appear = 2 + 1 = 3 (2^0, 2^1, 2^2)
\n" ); document.write( "# of ways factor \"7\" may appear = 1 + 1 = 2 (7^0, 7^1)
\n" ); document.write( "thus: # of ways these factors may be combined = 4*3*2 = 24
\n" ); document.write( "=> there are 24 factors \r
\n" ); document.write( "\n" ); document.write( "I HAVE ANOTHER QUESTION\r
\n" ); document.write( "\n" ); document.write( "I think i got a little lost. I got the last part, but how did you figure out that 756 = 3^3 *2^2 *7? Where did you get the numbers from. And also one last question, I would know that there are 24 numbers, but how would i know which ones will be the divisors?
\n" ); document.write( "And thanks again
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Algebra.Com's Answer #134580 by Mathtut(3670)\"\" \"About 
You can put this solution on YOUR website!
756=2*2*3*3*3*7
\n" ); document.write( ":
\n" ); document.write( "start with a known prime factor such as 2(since this is and even number) and then factor out all the primes.
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\n" ); document.write( "If you know rules of divisibility use those.The digits of this number 7+5+6=18 which is divisible by 9 so we know this number is divisible by 9.
\n" ); document.write( ":
\n" ); document.write( "and just keep working it down with as big of numbers as you can.
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