What is the Cardinality of a Set? | Set Theory, Empty Set

What is the cardinality of a set? In this video we go over just that, defining cardinality with examples both easy and hard. To find the cardinality of a set, you need only to count the elements in the set. The cardinality of the empty set is 0, the cardinality of the set A = {0, 1, 2} is 3. The cardinality of a set A is written |A|.

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I hope you find this video helpful, and be sure to ask any questions down in the comments!

[v.v.m]

I have learnt more in the first 45 seconds than I did in the ~33 minutes of my teacher trying to explain this simple concept. Thanks.

[Repriserey]

Thank your for this video! Now I learned this lesson more enough and now i have something to do at my Exam Tommorow.

[cooljazzy]

You're such a wonderful teacher. I like you how your instruction is clear and easy to follow. In fact, in less than 4 minutes you make me feel Luke i could actually get math. That's so weird ( in a good way ofcourse). Thank you!

[AA-emlw]

Bro, You are awesome, I mean it. Why do teachers make them so difficult for students at universities?
Thank you for the clear explanations.

[hemalatanayak]

Thank you for your help sir .
I just wanted to know what the bar thing is called but now I both know and understand what is cardinality of set.😊

[ibrahimbaras]

we reached 2022 and until now no one knows why the teachers in Youtube wayyyy better than the university, this teacher is an example with cadinality one pencell

[leisterfamilyleister]

Thank you for these videos! I totally understand the way you teach. - Tina

[jeffreydwightryanriley]

Omfg this is why I like php because it allows the use of objects. Math is my new love.

[K_ingh]

i was struggling with this.

Let A={a, b, c, d, e} and B = {d, e, f, g, h, i}.

The cardinality of the set |BxA\AxB| is:

thought it was 30 but its 26 but dont know how

[guillermomolinamatus]

Thanks this helped a lot. Simple and straight to the point.

[cantaimoncontroller]

Thx for the vid, gotta say teachers should teach the way you do

[virtuality]

What should we do in terms of repeated numbers. We count 1 or 2??

[TenorSaxx]

I love the way that you get to the point! Subscribed!

[markovujanic]

thanks for the great and clear video. I always though that empty set is part of every set, meaning every set would have cardinality of element + 1 (empty set)?

[SHACKYJOKER]

by the way what happen when a set has a a squared or cubed does it count as a part of the cardinality {3, 6^2, }

[AndreDV]

can u answer these questions please?
Write the cardinality of each set.
M = m is a month
S = {Word, Excel, PowerPoint, Publisher}
N = {10, 15, 20, 25, 30, 35, 40, 45, 50}
C = c is a continent
R = r is a prime number less than 23

[AvinashChandraPandey]

Two finite sets A and B are such that the total number of subsets of A is 56 more than the total number of subsets of B. What are the cardinalities of A and B respectively?

[HiROMZYyy]

Hi, I am just wondering if there is something like A = {a, a, b, c} where elements are overlapped. Will its |A| still be 4?

[tylee]

I was bad at math but i needed to learn as i get older that's why this helped me thank you!

[kaitlinbarrett]

I had no clue how to do this in my college math you