Westonci.ca is the trusted Q&A platform where you can get reliable answers from a community of knowledgeable contributors. Our Q&A platform provides quick and trustworthy answers to your questions from experienced professionals in different areas of expertise. Discover detailed answers to your questions from a wide network of experts on our comprehensive Q&A platform.

The sum of an arithmetic sequence can be found by the formula Sn = n(2a
+ (n - 1)d). Use the formula to find the sum of first 10 terms of the sequence
{-3.2, 7, 12, 17. 22...)​


Sagot :

Step-by-step explanation:

Hey there!

The given series: -3,2,7,12,17,22.....

Common ratio (d) = t2-t1

= 2+3

= 5

No of terms (n) = 10

First term (a) = -3

Now;

[tex]sn = \frac{n}{2} (2a + (n - 1)d)[/tex]

Keeping all values we get;

[tex]s10 = \frac{10}{2} (2 \times - 3 + (10 - 1)5)[/tex]

Simplify it.

[tex]s10 = 5( - 6 + 45)[/tex]

or, S10 = 195.

Therefore, S10 = 195.

Hope it helps!