document.write( "Question 171676: in the sequence 1, 6, 15, 28, 45 and so on, the nth term of the sequence is given by a quadratic polynomial, an^2+bn. what is the ordered pair (a,b)? \n" ); document.write( "

Algebra.Com's Answer #126832 by Edwin McCravy(20055) $\"\"$ $\"About$

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\n" ); document.write( "in the sequence 1, 6, 15, 28, 45 and so on, the nth term of the sequence is given by a quadratic polynomial, an^2+bn. what is the ordered pair (a,b)?
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document.write( "This means when\r\n" );
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document.write( "n=1, then term #1 = 1, that is, \r\n" );
document.write( "n=2, then term #2 = 6, that is, \r\n" );
document.write( "n=3, then term #3 = 15, that is, \r\n" );
document.write( "n=4, then term #4 = 28, that is, \r\n" );
document.write( "n=5, then term #5 = 45, that is, \r\n" );
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document.write( "We can take any two of those equations as a system, and\r\n" );
document.write( "solve for  and \r\n" );
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document.write( "We might as well take the easiest two, which are the\r\n" );
document.write( "first and second equations, although we could take\r\n" );
document.write( "any two of them as a system:\r\n" );
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document.write( "simplifying:\r\n" );
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document.write( "Solve this system of equations and get  and \r\n" );
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document.write( "So the ordered pair  \r\n" );
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document.write( "Edwin

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