# Cardinality of the statement

Discussion in 'Advanced Applied Math' started by suste88, Jan 24, 2020.

1. ### suste88

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What is the cardinality of this statement { x|x is a string over {a, b, c} and |x| <= 2}

suste88, Jan 24, 2020
2. ### MathLover1

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The set described is { a, b, c, aa, ab ,ac, ba, bb, bc, ca, cb, cc} over |x| <= 2

and this set has cardinality 13 because there are 13 things in it

MathLover1, Jul 14, 2021
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3. ### nycmathguy

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Wow! I didn't know that you can do sets. Impressed. You know set theory? This is something for me to explore in the future after calculus 3.

nycmathguy, Jul 17, 2021
4. ### MathLover1

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first time I learned about sets is in high school, 1965-69

MathLover1, Jul 17, 2021
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5. ### nycmathguy

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There is a course called Set Theory, which is not the same as high school sets.

nycmathguy, Jul 17, 2021
6. ### MathLover1

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of course college set theory is more complex (nowadays considered as a foundation of all other branches of math , and the mathematical science of the infinite), and not same as high school

MathLover1, Jul 17, 2021
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7. ### nycmathguy

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It's an interesting course but not so easy to grasp.

nycmathguy, Jul 17, 2021
8. ### MathLover1

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MathLover1, Jul 17, 2021
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9. ### nycmathguy

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Thanks for the link. However, I want to study one course at a time. Note: suste88 didn't thank you for your effort and reply here. This is what I'm talking about. Boring site. You know what, I will post some questions for you. Maybe you are bored? Let me look for some questions that I don't know how to solve in the David Cohen precalculus textbook. Look for 3 or 4 questions in about 15 minutes.

nycmathguy, Jul 17, 2021
10. ### MathLover1

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MathLover1, Jul 17, 2021
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11. ### nycmathguy

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The basics of set theory is part of precalculus not the entire set theory course. Set theory is very intense at the college level. I can solve some basic set theory problems but this does not mean that I know the actual set theory course.

nycmathguy, Jul 17, 2021

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