Find the sum of the terms in the arithmetic sequence below, {eq}S_n {/eq}.

{eq}7, 4, 1, -2, ..., -47 {/eq}

Question:

Arithmetic Sequence:

In mathematics, an arithmetic sequence is a list of number that is arranged in a way such that the difference between two consecutive numbers is always same or constant.

The {eq}{n^{th}} {/eq} or the last term {eq}(l) {/eq} of an arithmetic sequence is:

{eq}l = a + (n - 1)d {/eq}

The sum {eq}({S_n}) {/eq} of the terms in an arithmetic sequence is:

{eq}{S_n} = \dfrac{n}{2}(a + l) {/eq}

Here,

• The first term is {eq}a {/eq}.

• The last term is {eq}l {/eq}.

• The total number of terms is {eq}n {/eq}.

• The common difference between two terms is {eq}d {/eq}.

Answer and Explanation: 1