Writing arithmetic series in sigma notation

Courses on Khan Academy are always 100% free. Start practicing-and saving your progress-now: www.khanacadem...
Writing arithmetic series in sigma notation

[@adgf1x]

n=200. S=100(7+405)=41200

[@squishywaifu]

3:25 because 2-1 is 2

[@xxoctixx]

ermm😂😂😂😂

[@myrandomtantrum]

Im so confused....😖

[@saladking2370]

2:53 made it more confusing than it had to be

[@kjxnz]

Ikr I hate it here

[@sikothugie5609]

😂😂😂

[@ElidaKadwa-ln6ix]

😂😂😂eeh

[@Hetalmajithia]

2:54 so,there is a formula - "a+(k-1)d" where 'a' is first number means 7 and 'd' means difference means 2

[@AayushChitnis]

Man U guys just make everything soooooooo
Hard

[@cluezieys]

I was left more confused after this video😅 appreciate the vid though

[@leonardsitchon4864]

Thank you it became more easy

[@kyleherceda709]

Thank you very much

[@nij1107]

What if it starts with 405 and ends with 7?

[@tracerhax]

The sigma notation will be the same and the function will be: 405-2k

[@lilyg_miaw5160]

🗿Sigma🗿

[@dusty1374]

3:58 u did a mistake there

[@rachaelpanzenbock7521]

Omg, bless you

[@lisakhanya_x]

Doesn't 7 supposed to be negative?

[@sSacreed]

THANK YOU

[@DENNIEKLAhhneey]

Okay so where did you get that random 7? I'M SO CONFUSED pls

[@Hetalmajithia]

You have to take first number of series that's why he took 7

[@mo4098]

Khalman San you're so epic

[@angeliekylenunez9632]

thank youuuu dhjsccjscs, my problem is now solved

[@shelliebelle3710]

Can you simplify the bottom equation and just simply leave it at that?

[@jiggly821]

You should simplify, yes.

[@tosh3888]

Sigma 😏

[@julianarens3908]

great, thank you

[@I6e6ream]

Couldn't you do (5+2k)???

[@samvelk.3687]

May we write on the bottom of sigma charachter i=7 top - n=405 and on right - i+2 ?

[@TheNetflixGamer]

The top and bottom numbers refer to the starting and ending term number, like how 199 is the 199th term in the sequence

[@jasonstewart2981]

Nevermind...I jumped the gun

[@jasonstewart2981]

Shouldn't that be 200? There's 200 integers...

[@yasmeenb7648]

What’s K, I thought it was i or n

[@MrDegamus]

You can use any kind of variable there

[@ian.ambrose]

@@MrDegamus wanna fight?

[@MrDegamus]

@@ian.ambrose nah I'm good, thanks for asking tho

[@ArnoldPorcupine]

helped a lot

[@gamestorm1721]

1ST!!!!!

[@alexandrugheorghe5610]

So k=1 ?