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| Two ways (Posted on 2013-10-31) |
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Show that if N is a positive integer, then
C(2N,2)= 2*C(N,2)+ N^2
(a) using a combinatorial argument.
(b) by algebraic manipulation.
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Submitted by Ady TZIDON
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Rating: 3.6667 (3 votes)
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Solution:
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(Hide)
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1.Consider n girls and n boys trying to nominate 2 representative, disregarding their genders.
2.See either Jer's or MM's explanation. |
Comments: (
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Subject |
Author |
Date |
 | Ways | Math Man | 2013-11-01 19:35:32 |
| Solution | Jer | 2013-11-01 08:18:40 |
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