Written work, Due Thursday, October 17th, in class:
Chapter 4 p.100: 1, 6, 7, 15, 16
Odd problems are worth 4 points, even problems worth 8 points.
WeBWorK – none
OpenLab – OpenLab #5 Due Thursday 10/24. NOTE: Please complete the writing portion on the OpenLab, but bring your Conjecture to class on 10/24 (do not post your Conjecture to the OpenLab)
Tag: assignments
Week 5 Assignments
NOTE 1: Exam #1 will take place on Thursday, 9/26 (first half of class).
NOTE 2: Next week Tuesday 10/1 there are no classes at City Tech.
NOTE 3: The following week Tuesday 10/8 there are no classes at City Tech.
Written work – none
WeBWorK – Assignment #4, due Thursday, October 3rd, at midnight. You are encouraged to start working on Assignment #5, which will be due one week later.
OpenLab – OpenLab #4: Bridges and Walking Tours due AT START OF CLASS on Thursday, 10/10.
Week 4 Assignments
UPDATE: WeBWorK Assignment #4 will be due next week, Thursday 10/3.
Written work – none
WeBWorK – Assignment #3 and Assignment #4, due Tuesday, September 24th, at midnight.
OpenLab – none
STUDY – for your first exam, taking place on Thursday, September 26th, during the first hour of class. A review sheet will be posted at least 1 week prior to the exam.
Logic on Math StackExchange
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- Is the inference rule another notation for $\implies$? April 18, 2024In mathematical logic, when we write a formula of the metalanguage (such as $A \vdash B$) above an horizontal rule and another formula (such as $\vdash A \to B$), is it the same as writing a meta implication sign $\implies$ between the two formulas?Anserin
- Prove that if a frame is dense then $\Box \Box A \to \Box A $ is valid [duplicate] April 18, 2024I am having trouble with the following question on modal logic. A modal logic frame $M =\langle W, R\rangle$ is dense whenever $$\forall x\forall y(Rxy\rightarrow\exists z(Rxz \land Rzy))$$ Prove that the formula $$\Box\Box A\to\Box A $$ is valid in every dense frame. We don't make any assumptions about the frames. How can this be done?A_alk
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