geometric series formula

Is there any tips to learn geometric series formulas ? I always forget them and keep looking up online. when exams come, I tried to learn them at the time then forgot them again. also is there any good website which provides fully useful ones.
thank you

Reply 1

Zacken

Original post by vanessa_tram

Why don't you derive them? That should be a good way of embedding it in your mind?

Reply 2

vanessa_tram

Original post by Zacken

Why don't you derive them? That should be a good way of embedding it in your mind?

when it comes to sum from 0 or 1 to infinity i'm always stuck. i never like "infinity" to be honest. lol

Reply 3

Zacken

Original post by vanessa_tram

when it comes to sum from 0 or 1 to infinity i'm always stuck. i never like "infinity" to be honest. lol

Do you know the one to n terms? Just let

n \to \infty

Reply 4

vanessa_tram

Original post by Zacken

Do you know the one to n terms? Just let

n \to \infty

oh, i see what u mean, ok, i will try that. thank you :smile:

Reply 5

HapaxOromenon2

Original post by vanessa_tram

Original post by Zacken

Why don't you derive them? That should be a good way of embedding it in your mind?

They're given in the formula booklet which you get given a copy of in each exam! (Though of course it is good to learn them by heart as it saves time...)
Edexcel Formula Booklet: https://qualifications.pearson.com/content/dam/pdf/A%20Level/Mathematics/2013/Specification%20and%20sample%20assessments/N38210A-GCE-Mathematical-Formulae-Statistical-Tables.pdf
AQA Formula Booklet: http://filestore.aqa.org.uk/subjects/FORMULAE.PDF
OCR MEI Formula Booklet: http://www.mei.org.uk/files/pdf/formula_book_mf2.pdf
OCR Non-MEI Formula Booklet: http://www.ocr.org.uk/Images/70824-datasheet-examination-formulae-and-statistical-tables.pdf

Reply 6

Zacken

Original post by HapaxOromenon2

I think she's a uni student.

Reply 7

vanessa_tram

Original post by HapaxOromenon2

thank you but im doing undergraduate. my uni dont give any formula booklet for this :frown:

Reply 8

HapaxOromenon2

Original post by vanessa_tram

thank you but im doing undergraduate. my uni dont give any formula booklet for this :frown:

If you're an undergraduate then how the hell don't you know these basic formulae already? I guess you must be studying at some random "university" with no credibility.

Reply 9

vanessa_tram

Original post by HapaxOromenon2

If you're an undergraduate then how the hell don't you know these basic formulae already? I guess you must be studying at some random "university" with no credibility.

Excuse me? I may not know everything but I ask nicely and I learn. But u, even a basic thing u don't even know "how to be polite"

Reply 10

Zacken

Original post by vanessa_tram

Excuse me? I may not know everything but I ask nicely and I learn. But u, even a basic thing u don't even know "how to be polite"

He's a troll, please ignore him.

Reply 11

username1560589

Original post by vanessa_tram

Maybe remember the factorisation

1-x^n = (1+x+x^2+...+x^{n-1})(1-x)

.
Or just derive it fully.

Reply 12

HapaxOromenon2

Original post by Zacken

He's a troll, please ignore him.

Cease and desist from defaming me immediately. I am simply stating that someone who cannot remember basic A-Level formulae ought not to be doing a mathematics or mathematics-related university course. You can disagree with that view if you wish, but do not dare to insinuate that I act with anything other than full seriousness.