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21. Some Special Series
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Q4 of 60 Page 21

If , find .

………….. (1)


Given



From (1) we have



Solving the above equation


n = 10


We know


………(2)


Thus


Putting n = 10 in eq(2)



= 552


= 3025


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2

Write the sum of the series : 12 – 22 + 32 – 42 + 52 – 62 + ……. + (2n – 1)2 – (2n)2

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Questions · 60
21. Some Special Series
1 2 3 4 5 6 7 8 8 8 8 9 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 9 10
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