document.write( "Question 965979: prove that the product of any three consecutive numbers is even.
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document.write( "So far I have tried , (n)(n+1)(n+2)=n^3+3n^2+2n
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document.write( "but there is no multiple of an even number. I'm not sure what kind of proof method it is but this would be a proof with the same method. i.e prove that the sum of three consecutive odd numbers is divisible by 3 , 2n+1+2n+3+2n+5= 6n+9 3(2n+3) is a multiple of three therefore it is divisible by three.\r
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document.write( "Any help would be appreciated, hope it is not too confusing
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document.write( "Thanks
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Algebra.Com's Answer #590410 by tenkun(12)![]() ![]() ![]() You can put this solution on YOUR website! let the consecutive numbers are n,(n+1),(n+2) \n" ); document.write( "product = n*(n+1)*(n+2)\r \n" ); document.write( "\n" ); document.write( "if n=1 \n" ); document.write( "P(1) = 1*2*3=6 --Even \n" ); document.write( "Assume that P(n)=even then we have to prove that P(n+1)=(n+1)*(n+2)*(n+3) is also even\r \n" ); document.write( "\n" ); document.write( "P(n+1)= (n+1)*(n+2)*(n+3) \n" ); document.write( " =n*(n+1)*(n+2)+ 3*(n+1)*(n+2) \n" ); document.write( "we know that n*(n+1)*(n+2)is even ( assumed ) \n" ); document.write( "we have to show that 3*(n+1)*(n+2) is also even \n" ); document.write( "if n is odd then n+1 is even \n" ); document.write( "either way n^2+3*n+2 is even \n" ); document.write( "so 3*(n+1)*(n+2)=3*(n^2+3*n+2) is also even \n" ); document.write( "we have shown that P(1) is even and that P(n+1)is even if P(n)is even. \n" ); document.write( "hence proved. \n" ); document.write( " |