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What is the sum of the series 1- 1 2 + 1 4 - 1 8 + equal to?

Options

  1. A1/2
  2. B3/2
  3. C2
  4. D2/3

Correct answer

D. 2/3

Step-by-step solution

aligned & 1, -1 2 , 1 4 , -1 8 & ~S _ = a 1-r r=-1 / 2 & a=1 = 1 3 . aligned

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