Geometric Sequence (Explicit Formula)

Learn how to write an explicit formula for a geometric sequence in this free math video tutorial by Mario's Math Tutoring.

0:11 What is a Geometric Sequence
0:39 What is the Ratio
0:52 How to Identify the Term and the Term Value
1:21 How to Find a Specific Term in 3, 6, 12, 24, 48,...
2:14 Formula for a Geometric Sequence
3:23 Example 2 80, -20, 5, -5/4,... Find a Formula for the Sequence
4:25 How to Find the Ratio

Related Videos:

My Sequence and Series Video Playlist

Arithmetic Sequence Formula

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[kiarawalker]

Thankyou sooo much like my teacher is HORRIBLE and I’ve struggled with this lesson ever since he’s introduced it to us... but thanks to you I got a 100 on my algebra quiz on this lesson!!😁😁😁😁😁😁😅

[kaikwondo]

Most informative math video I've ever seen. My math teacher thinks shes all that, but she honestly sucks and takes WAY to long to explain stuff. I end up just zoning out half way through her explaining how she chose the theme of the homework. This helped more than you could ever know! Thank you!!

[vengeanceos_]

EFFICIENT AND CONCISE. Learned more in 40 seconds than in a 12 min video

[SaritaLaroche]

My son got stuck on a zoom assignment only in audio today (no whiteboard) and just couldn't understand what the teacher was saying and how to do his work today. In about 2:20 he had it all figured out with you. Thank you.

[Hello-fwpi]

I forgot how to do this cause the formula was hard to remember, especially the N and R value but thanks to this video it helped me remember, thanks!

[juanaguilar]

Straight to the point again! Really appreciated.

[ppcaca]

dude my math teachers explains stuff so fast i don’t understand, u explained it well! thx man 👍

[ethanolol]

Thanks so much we’re covering this right now in class

[sumi]

thanks for explaining. i have a math exam today at 10:00am.

[AprilMeep]

I spent a whole day trying to figure this out and you just made it so simple! Thank you.

[daxxonhauser]

I've been struggling with this and this really helped me out! Thanks!

[thefishreloaded]

Thanks, I have trouble with all to do with exponentials, so this was VITAL.

[llamanugget]

because of you I got a 100 on my unit test :) thanks a lot!!!

[micxssereno]

tbh- out teachers arnt bad, we just dont listen, and we understand this vid because its either our exams are tomorrow or we have a homework to do- but still yeah tnx mariooo i actually got it HAHAHAHA

[aaliyah]

no one:

the ad before the video started: "what you're still searching for youtube videos for math help?"

me: 👁👄👁 yes

[mogged]

Professor Mario, please recommend me some good highschool math textbooks

[samuelgalarcemoscoso]

i have a question. the final formula is the simplified form of the explicit formula for geometric sequence? please mario respond my question the homework is for tomorrow

[dreams]

Thank you I’m taking summer school and this really helped

[lspellslogic]

Thanks a lot. But how do you make an explicit formula for {3, 9, 21, 45} ? I've been struggling on this one for days and everywhere I read there seems to be no way to solve it

[hernancostal]

whats the difference between writing f(n) and A(n)?