<PRE><B>Question 209751</B>
.Write the first six terms of the sequence that starts with 1, and for which the difference between consecutive terms is first 2, and then 3,4,5, and 6.
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1,3,6,10,15,21
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b.Evaluate (n^2+ n) /2 for n=1,2,3,4,5 and 6.
Compare the sequence you get with your answer for part a.
If n = 1 you get (1+1)/2 = 1
If n = 2 you get (4+2)/2 = 3
If n = 3 you get (9+3)/2 = 6
etc.
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c.Draw a diagram to represent (n squared +n)/2 for n=5.
(25+5)/2 = 15
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Cheers,
Stan H.
Reply to stanbon@comcast.net
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