Find the sum of first n natural numbers.

1.	Find the sum of first n natural numbers.
Answer» For the given AP the first term a is 1, and common difference d is a difference of the second term and first term, which is 2 - 1 = 1 To find : the sum of given AP The formula for the sum of AP is given by, s = \(\frac{n}{2}\)(2a+(n-1)d) Substituting the values in the above formula, s = \(\frac{n}{2}\)(2+(n-1)(1)) s = \(\frac{n(n+1)}{2}\)

Answer»

For the given AP the first term a is 1, and common difference d is a difference of the second term and first term, which is 2 - 1 = 1

To find : the sum of given AP

The formula for the sum of AP is given by,

s = \(\frac{n}{2}\)(2a+(n-1)d)

Substituting the values in the above formula,

s = \(\frac{n}{2}\)(2+(n-1)(1))

s = \(\frac{n(n+1)}{2}\)

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