# How do you find the first three terms of the arithmetic series #a_1=17#, #a_n=197#, and #S_n=2247#?

##### 2 Answers

**First three terms are**

#### Explanation:

And number of terms is

Mid term is

Sum

First three terms are

#### Explanation:

An arithmetic sequence is the one in which the difference of the successive terms is the same

For example,

Now lets solve the problem. For that we use the formula

#color(green)(S_n=n((a_1+a_n)/2)#

Where,

Now we know that the

To find the common difference, we use

#color(green)(a_n=a_1+(n-1)d#

Now we have come to an end to the answer. We add

#color(purple)(17,26,35....#

Hope this helps!!! ☺