The sum of first n terms of the series. 1 – 1 + 1 – 1 + ... is

Mathematics · JEE Main · NTA Exams — Progression and Series

1. 1 if n is odd and 0 when n is even
2. –1
   
3. (–1)ⁿ
4. ± 1

Answer

(A) 1 if n is odd and 0 when n is even

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