Discrete Math - 1.6.2 Rules of Inference for Quantified Statements

[@johnboy2656]

I could literally cry. These videos have made so much sense to me! My teacher is not the best, so these videos have been absolute life-savers! Thank you, Professor Brehm!

[@GalGalK]

Literally a queen, helping students all over the world. What a wonderful person, I hope you realize how much this helps me, and how much I talk back to the screen when you aska question haha. Thank you Professor B!

[@SawFinMath]

Haha I love that visual! I can almost hear you answering my questions :)

[@kairu9373]

That one student who passed the Discrete Math class without reading the book must've been De Morgan.

[@SawFinMath]

Haha

[@blackbolato]

Thanks i feel less stupid having this explained to me rather than reading it myself. Honestly great video.

[@aminakhan1195]

I understood every proof question including the indirect proof, only from your channel. YOU ARE AMAZING!

[@JeepDude]

This gave me some much needed practice exercises. You said many helpful things, such as keep the end in mind, and look to simplify.

[@WillowElysium]

I have to get a B in discrete to stay in my major path, you're literally an angel

[@KnowledgeIsGold]

Hi, for 10:52. For the premises, there's always a check to see if x is a student in discrete math. So my question is, why isn't there a check on the conclusion statement? Can it be ∃x (d(x) ^ p(x) ^ ¬b(x))?

[@nazarmirza1838]

My exact thought, I'm stuck at this. Have you figured it out? 😅

[@dlafont256]

Very clearly explained. Thank you!

[@shanciewagner1527]

I really like this. You are a great teacher. Can I get the textbook with the problems in it? What is the title?

[@SawFinMath]

Rosens Discrete Mathematics

[@godzab]

The only reason why the student passed the class without reading the book was because they watched your videos.

[@oudeemail6115]

You helped me pass my retake thank you

[@egehanyildiz]

hello dear teacher in the problem at 6:30 can we just say that F(X) denotes x is a dog that has 4 legs and then just use Universal instantiation or is it necessary to split F(x) into 2 parts like x has 4 legs and D(X) is a dog

[@Vincentvangoat7]

you saved me

[@mohammedehab6840]

3ash sobhy

[@youssefyoussef3652]

@@mohammedehab6840 hahaha 3ash sobhy & mohammed

[@mohammedehab6840]

@@youssefyoussef3652 habeeby

[@shalahe]

ya Qedme ya alm3rb (THis is literally Arabic 😅)

[@mohob-b6r]

نتفرج عليها كويسه ولا ايع يا شباب

[@spino19]

Thank you so much, this was insanely helpful!!!

[@NISCHALGYAWALI-b7t]

Awesome Content

[@frankiechina329]

Why didn’t the conclusion at 11:02 have a d(x)? 🤔

[@jokingpirate]

I'm kinda late , but it's Because they cancel each other

[@AbeihHamani]

very good video, but could we have not used like universal modus ponen on the first question by any chance?

[@ryuuboruzs]

At 9:15 I would like to say that the equation should look like Ǝ(x) D(x) /\ P(x) --> eg B(x) (Left side) (Right side) Ǝ(x)D(x) --> eg B(x) \/(For all of (x)) D(x) --> P(x) Then I distributed and crossed out and solved where I got egB(x) --> egB(x) for both sides and can substitute what I need for the sentence. I'm not sure how you wrote the equations with and in them when the sentences showed equals to 'not reading a book' So I am curious if my way is also correct. If anyone or Kimberly knows, I'd like an answer.

[@seeulater8753]

The video overall was very well indeed. However, I have a question: Isn't that supposed to be ∃x (d(x) ^ p(x) ^ ¬b(x)) don't we need to specify the domain by D(x) here?? at 10:40

[@asura9161]

I was confused here as well. When i first wrote out the premises I left D(x) as the domain so that i wouldnt include with the quantifiers.

[@farhadrasooly4864]

great!! you helped me a lot!!! Thank you so much

[@Wakethenoob]

couldn't we have done UMP on step four and step 3 to reduce the steps and and still gotten the same answer? 16:21

[@youssefyoussef3652]

Totally clear, Thanks.

[@soulexesns9522]

THANK YOU SO MUCH

[@kwam7373]

kimberly brehm is up on professor lenard's level this is amazing. will there be a calc3 course?

[@SawFinMath]

Probably not for a while, unless I get a lot of requests.

[@maksymandrzejdrzyzgiewicz5096]

NOBODY is on Leonard's level! But that's not to say that prof. Brehm isn't great!

[@Lucas-po6mn]

You're the GOAT 🐐

[@mohammedadam85]

Hi there Thank you for these lecture they are very helpful last year I stopped my Uni because I could not understand this Subject. this year I am sure I will pass it. I was wondering if you can give me the name of the text book you have mentioned in this lecture. Many thanks again for these wonderful explanation for these subject .

[@SawFinMath]

This text is Discrete Mathematics and It’s Applications by Rosen.

[@mohammedadam85]

@@SawFinMath Thank you very much .

[@prammar1951]

Thnx very helpful series. Just curious, ever tried programming in prolog? It is a logic programming language, i am studying this series to become better at it, tho can't see why anyone would use prolog instead of one of the mainstream languages like python and c++

[@osrlazlo-m7d]

For the practice problem, and problems in general, if the domain is not specified, am I allowed to set my own domain? I set my domain to "students in discrete math", which make D(x) always true, and that simplifies the problem a lot.

[@SawFinMath]

If it kinda feels like cheating, it is :). You are asked to use implications, conjunctions, and/or disjunctions using quantifiers. That isn’t what you did.

[@zzzzzzzjsjyue2175]

I don’t understand the universal generalization rule. Why is p(x) true for all values if it’s true for an random c?

[@_kevin_wong_]

so helpful thank you!

[@nicolaslab573]

Can someone help me understand why we need D(x) in the "someone who passed the class" one? I would've thought that x was the student, what is the predicate there? I don't see anywhere in the text "a person is a discrete math student" or something. Isn't it a given?

[@sodakaidotcom]

But not all dogs have four legs.

[@bayan445]

thank u 💜

[@danlupu5943]

For the last challenge, could you not just state your domain of discourse is the class and make it much simpler? Or did you not do it so you could show the different rules and simplify the expression or show how you arrived at the conclusion?

[@bigdrugulent1400]

Why cant i just set the domain for x to students in discrete math class and then just use conjunction with my 2 premises

[@AeshaMehveen]

hi i have a DM exam in a few days and im stuck on a problem. is there a way i can reach you to send you the question?

[@SawFinMath]

I can’t make any promises, but you are welcome to email me [e-mail]

[@bash7638]

I love youuuuuuuuu

[@zzzzzzzjsjyue2175]

Actually I don’t really understand the difference between universal generalization and existential generalization. Don’t they say the same tjing

[@christiantapasao4944]

Is this rules of inference in predicate logic?

[@SawFinMath]

I think you're looking for 1.6.1. This one would be next in line, as it uses 'For all' and 'There exists'

[@parsasamandi569]

I don't know how to thank you

[@in3briatedclown845]

if every X is like a spider with the center being the body then every X has 4 legs. Sorry, I like making dumb comments.

[@Zoooooooooooo]

i love you woman

[@harshdeepsingh1666]

Chup mahgya amoro heigola

[@parsasamandi569]

I don't know how to thank you

[@SawFinMath]

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