Discrete Math - 1.6.2 Rules of Inference for Quantified Statements

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  • เผยแพร่เมื่อ 18 ธ.ค. 2024

ความคิดเห็น • 63

  • @johnboy2656
    @johnboy2656 8 หลายเดือนก่อน +8

    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
    @GalGalK 2 ปีที่แล้ว +55

    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
      @SawFinMath  2 ปีที่แล้ว +11

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

  • @kairu9373
    @kairu9373 3 ปีที่แล้ว +83

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

  • @aminakhan1195
    @aminakhan1195 4 ปีที่แล้ว +21

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

  • @blackbolato
    @blackbolato 2 ปีที่แล้ว +9

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

  • @JeepDude
    @JeepDude 4 ปีที่แล้ว +19

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

  • @KnowledgeIsGold
    @KnowledgeIsGold 2 ปีที่แล้ว +7

    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
      @nazarmirza1838 7 หลายเดือนก่อน +1

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

  • @frankiechina329
    @frankiechina329 2 ปีที่แล้ว +4

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

    • @jokingpirate
      @jokingpirate ปีที่แล้ว +1

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

  • @dlafont256
    @dlafont256 3 ปีที่แล้ว +5

    Very clearly explained. Thank you!

  • @shanciewagner1527
    @shanciewagner1527 9 หลายเดือนก่อน +1

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

    • @SawFinMath
      @SawFinMath  9 หลายเดือนก่อน

      Rosens Discrete Mathematics

  • @seeulater8753
    @seeulater8753 2 ปีที่แล้ว +1

    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
      @asura9161 3 หลายเดือนก่อน

      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.

  • @egehanyildiz
    @egehanyildiz ปีที่แล้ว +1

    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

  • @oudeemail6115
    @oudeemail6115 ปีที่แล้ว

    You helped me pass my retake thank you

  • @Wakethenoob
    @Wakethenoob 3 หลายเดือนก่อน

    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

  • @Vincentvangoat7
    @Vincentvangoat7 4 ปีที่แล้ว +4

    you saved me

    • @mohammedehab6840
      @mohammedehab6840 3 ปีที่แล้ว +1

      3ash sobhy

    • @youssefyoussef3652
      @youssefyoussef3652 3 ปีที่แล้ว +1

      @@mohammedehab6840 hahaha 3ash sobhy & mohammed

    • @mohammedehab6840
      @mohammedehab6840 3 ปีที่แล้ว +2

      @@youssefyoussef3652 habeeby

    • @shalahe
      @shalahe 2 ปีที่แล้ว

      ya Qedme ya alm3rb (THis is literally Arabic 😅)

    • @davinho-b6r
      @davinho-b6r ปีที่แล้ว

      نتفرج عليها كويسه ولا ايع يا شباب

  • @osrlazlo-m7d
    @osrlazlo-m7d 2 หลายเดือนก่อน +1

    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
      @SawFinMath  2 หลายเดือนก่อน

      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.

  • @ryuuboruzs
    @ryuuboruzs 3 ปีที่แล้ว

    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.

  • @spino19
    @spino19 ปีที่แล้ว

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

  • @godzab
    @godzab ปีที่แล้ว +1

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

  • @NISCHALGYAWALI-b7t
    @NISCHALGYAWALI-b7t ปีที่แล้ว

    Awesome Content

  • @zzzzzzzjsjyue2175
    @zzzzzzzjsjyue2175 2 ปีที่แล้ว +1

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

  • @farhadrasooly4864
    @farhadrasooly4864 2 ปีที่แล้ว

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

  • @nicolaslab573
    @nicolaslab573 6 หลายเดือนก่อน

    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?

  • @kwam7373
    @kwam7373 3 ปีที่แล้ว +3

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

    • @SawFinMath
      @SawFinMath  3 ปีที่แล้ว +3

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

    • @maksymandrzejdrzyzgiewicz5096
      @maksymandrzejdrzyzgiewicz5096 ปีที่แล้ว

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

  • @mohammedadam85
    @mohammedadam85 6 หลายเดือนก่อน

    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
      @SawFinMath  6 หลายเดือนก่อน

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

    • @mohammedadam85
      @mohammedadam85 6 หลายเดือนก่อน

      @@SawFinMath Thank you very much .

  • @bigdrugulent1400
    @bigdrugulent1400 10 หลายเดือนก่อน

    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
    @AeshaMehveen ปีที่แล้ว

    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
      @SawFinMath  ปีที่แล้ว

      I can’t make any promises, but you are welcome to email me kbrehm@bellevue.edu

  • @youssefyoussef3652
    @youssefyoussef3652 3 ปีที่แล้ว

    Totally clear, Thanks.

  • @christiantapasao4944
    @christiantapasao4944 2 ปีที่แล้ว

    Is this rules of inference in predicate logic?

    • @SawFinMath
      @SawFinMath  2 ปีที่แล้ว

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

  • @prammar1951
    @prammar1951 ปีที่แล้ว

    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++

  • @danlupu5943
    @danlupu5943 ปีที่แล้ว

    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?

  • @_kevin_wong_
    @_kevin_wong_ 3 ปีที่แล้ว

    so helpful thank you!

  • @soulexesns9522
    @soulexesns9522 7 หลายเดือนก่อน

    THANK YOU SO MUCH

  • @Lucas-po6mn
    @Lucas-po6mn 2 ปีที่แล้ว

    You're the GOAT 🐐

  • @zzzzzzzjsjyue2175
    @zzzzzzzjsjyue2175 2 ปีที่แล้ว

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

  • @bayan445
    @bayan445 ปีที่แล้ว

    thank u 💜

  • @bash7638
    @bash7638 2 หลายเดือนก่อน

    I love youuuuuuuuu

  • @parsasamandi569
    @parsasamandi569 2 หลายเดือนก่อน

    I don't know how to thank you

  • @in3briatedclown845
    @in3briatedclown845 หลายเดือนก่อน

    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
    @Zoooooooooooo 2 หลายเดือนก่อน

    i love you woman

  • @harshdeepsingh1666
    @harshdeepsingh1666 ปีที่แล้ว +1

    Chup mahgya amoro heigola

  • @parsasamandi569
    @parsasamandi569 2 หลายเดือนก่อน

    I don't know how to thank you

    • @SawFinMath
      @SawFinMath  2 หลายเดือนก่อน

      You already did by commenting and subscribing!