The sum 1 + 2 + 3 + ... + n is:

1. A n(n+1)/2 Correct answer
2. B n(n+1)
3. C (n+1)/2
4. D n²

Solution

Sum of first n natural numbers = n(n+1)/2.

About this question

Subject: Mathematics · Chapter: Sequences and Series · Topic: Special Series

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