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# Quick Algebra Problem

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1.) Compute $$1 - 2 + 3 - 4 + \dots + 2005 - 2006 + 2007$$

2.) Compute the sum $$\frac{2}{1 \cdot 2 \cdot 3} + \frac{2}{2 \cdot 3 \cdot 4} + \frac{2}{3 \cdot 4 \cdot 5} + \cdots$$

Thank you

Aiyan  Feb 25, 2017
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1)

1 - 2 + 3 - 4 + ..........2005 - 2006 + 2007

[-1 x 1008] + 2007 =1,009.

2) 2/6 + 2/24 + 2/60 +2/120 + 2/210 + 2/336 + 2/504 + 2/720.........etc.

F / [1 - R] = Sum

1/3 / [1 - 1/3] =1/2.

Guest Feb 25, 2017

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