document.write( "Question 557458: Mathematicians have been searching for a formula that yields prime numbers. One such formula was x^2-x+41. Select some numbers for x, substitute them in the formula, and see if prime numbers occur. Try to find a number for x that when substituted in the formula yields a composite number. \r
\n" ); document.write( "\n" ); document.write( "I'm not sure of the steps to complete this problem...Please explain.
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Algebra.Com's Answer #362674 by KMST(5328)\"\" \"About 
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The polynomial \"P%28x%29=x%5E2-x%2B41\" was supposed to yield prime numbers.
\n" ); document.write( "You are expected to try a few values for x , and find the corresponding P(x).
\n" ); document.write( "It is likely to be a prime number. Here are a few:
\n" ); document.write( "P(0)=41, P(1)=41, P(2)=43, P(3)=47, P(4)=53, P(5)=61, P(6)=71, P(7)=83, P(8)=97, P(9)=113, P(10)=131 P(20)=421, P(30)=971, P(40)=1601.
\n" ); document.write( "All of those (and \"P%28x%29\" for the \"x\" values in between) are prime numbers.
\n" ); document.write( "It was a nice try, the design of P(x) ensured that iy could not be a multiple of 2, 3, 5, 7.
\n" ); document.write( "However,
\n" ); document.write( "\"P%28x%29=x%5E2-x%2B41=x%28x-1%29%2B41\", so if \"x\" or \"x-1\" were a multiple of 41, \"P%28x%29\" would be a multiple of 41. So,
\n" ); document.write( "\"P%2841%29=41%2A40%2B41=41%2A%2840%2B1%29=41%2A41\"
\n" ); document.write( "\"P%2842%29=42%2A41%2B41=41%2A%2842%2B1%29=41%2A43\"
\n" ); document.write( "\"P%2882%29=82%2A81%2B41=2%2A41%2A81%2B41=41%2A%282%2A81%2B1%29=41%2A163\"
\n" ); document.write( "\"P%2883%29=82%2A83%2B41=2%2A41%2A83%2B41=41%2A%282%2A83%2B1%29=41%2A167\", and so on
\n" ); document.write( "There are other values of P(x) that are not prime, too, like
\n" ); document.write( "\"P%2845%29=2021=43%2A47\"
\n" ); document.write( "\"P%2850%29=2491=81%2A53\"
\n" ); document.write( "\"P%2866%29=4331=61%2A71\"
\n" ); document.write( "\"P%2877%29=5893=71%2A83\"
\n" ); document.write( "\"P%2885%29=7181=43%2A167\"
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