10371 1 1 12 3 4

3

:

10

3

7

1 1 1

1

2 3 4

...

2012

 

b) Tính

P

2011 2010 2009

1

1

2

3

...

2011

HD: Nhận thấy 2011 + 1 = 2010+2 = ….

2012

2010

1

MS

1

1

.... 1

2011

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 

 

1

2

2011

2012

2012

....

2012

2011

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2012(

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)

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2011

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2012

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100

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.

63

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c)

A

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