Written work, Due Tuesday, October 23, in class:
Chapter 4 p.100: 4, 5, 10, 11
Chapter 5 p.110: 1, 4, 9
Odd problems are worth 4 points, even problems worth 8 points.
WeBWorK – none
OpenLab – none
Tag: written work
Written work – None.
WeBWorK – Assignment #5, due Tuesday, October 9th, at midnight.
OpenLab – OpenLab #4, due Thursday, October 11th, before class.
Week 3 Assignments
Written work – None
WeBWorK – Start on WeBWorK 3, (it will not be due until Tuesday, 9/25 at midnight).
OpenLab – OpenLab #3, due Tuesday, 9/20 (at start of class).
NOTE: Next week Tuesday 9/18 there are no classes.
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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- Are there any problems about the difference between set theoretic definitions of polynomials? April 17, 2024I am a novice about this question, so if there is a misunderstanding then I apologize for it. As for Peano axioms, if I choose Zermelo natural numbers, and you choose von Neumann ones, then this doesn't cause any problems because we can prove Peano axioms are categorical i.e. it is guaranteed my model, and […]categoricalequivalent
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