Sum of an Arithmetic Series Formula

Learn how to find the sum of an Arithmetic Series in this free math video tutorial by Mario's Math Tutoring. We discuss use of the sum formula and go through some example problems.

0:17 Difference Between a Sequence and a Series
0:28 Formula for Sum of an Arithmetic Series
0:40 Example of Why and How the Formula Works
2:25 Example 1 Finding the Sum of an Arithmetic Series in Summation (Sigma) Notation
3:49 Trick for Finding the Number of Terms in a Summation
4:57 Example 2 More Challenging Example
5:40 Using the Explicit Formula for an Arithmetic Sequence

Related Videos:

Arithmetic Sequence Explicit Formula

Playlist for Sequences and Series

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[SUPERSAVERHEROgamer]

This was actually so beautiful, the way you explained how the formula works and why it works.

[bleepbloop]

thank you for explaining why the formula is the way it is, it always helps me as it suits my way of thinking

[gabombisabajombi]

Thank you so much, after watching this I just finished my assignment easily! I learned a lot from this 6 minutes than I had for 30 minutes in school.

[jarridkamphenkel]

Best video on the topic! thank you for using an uneven number example and showing how the numbers actually work!

[jewelmonsta]

Such a brilliant video, best explanation ever. Thank you!!

[jenajilbadiong]

thanks for the formulas, i don't even understand my modules ajskshs

[jacobgriner]

love your videos man. hope you get more publicity with the amount of great material you post.

[christianprinceranara]

the best video ever, easy to understand and very simple, keep it up sir. Thank you.

[rickgrimes]

I have 2 say ur helping me more than my teacher please keep doing this tnx

[josephkasai]

Best explanation ever any reference book please

[ankitaaarya]

Who ever thought of the first formula in that way is clever and brilliant

[jaylu]

Nice video sir...thanks because it helps me to solve faster the problems at math

[sydniesy]

For me, I won't divide 17 yet, I will get the answer first in the a sub 1 and last term, then I'll multiply that answer to 17 then divide it to 2 so it's like s17= 17/2 (14+62) = 17/2 (76) = 1292/2 so 1292÷2 is 646 so the answer is 646

[janella]

Thank you sir. It helped me a lot. But what if the given sequence is in descending order. How would it be? Hoping you notice this comment

[TheRatedRSuperstar]

You’re way better then my math professor lmao

[nico_lodeon]

do you have a video about how to get the n if you already have the sum, first term and last term?

[micahraney]

Great visual explanation of the formula! But, the answer should be 646 by my calculation.

[keshiaduplooy]

You. Are. Amazing. Thank you so much for this 💕💕

[steveharvey]

Sir what if the given sequence is

½, -⅓, -¾, -1, -7/6

How can I find the Sn? What formula do I need to use?