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_ n=1 ^ (-1)^n n+1 is equal to

Options

  1. Ae⁻¹
  2. B2-1
  3. C1
  4. D0

Correct answer

B. 2-1

Step-by-step solution

aligned _ n=1 ^ (-1)^n n+1 & =- 1 2 + 1 3 - 1 4 + & =1- 1 2 + 1 3 - 1 4 + -1 & = 2-1 aligned

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