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You are not logged in. #1 20130520 02:41:47
Mathematical Logic and Structures, URGENT!Hey guys, i need a HUGE favor, i need the resolution for this 5 questions, its a question of end this year my degree or stay one year just with a subject. Please I am begging, who knows the resolution please say me something. #2 20130520 03:28:55
Re: Mathematical Logic and Structures, URGENT!
I am not the world's expert on logic, but I am sometimes good at these sort of questions. Not sure what exactly is required by "convert the formula into prenex form". (Is this "prenex normal form" ?) If it is prenex normal form it may be a good idea to look at the Wikipedia info: http://en.wikipedia.org/wiki/Prenex_normal_form To me "prenex form" means 'there exists' (inverted E ?), 'for all' (looks like an A written vertically inverted) etc. also includes NOT, AND, OR, IMPLIES etc. in symbolic form. I included the "such that" bits to help me understand it, you have not included any because it is conventional to leave them out in prenex form I suppose. Or have I completely got the wrong understanding of the meaning of that question? What else is there to be done ? I am obviously missing something here. I think it is a bit mean asking students to convert something like that and memorise all the rules contained in that link for an exam. Are you revising for an exam ? How can something depend on the square root of z if z is not included in the predicate ? Clarification in LaTex: Is p(x,g) a predicate that does a test upon the variables x and g and gives a "true" or "false" ? Is q(x,y) similarly defined for x and y giving a "true" or "false" ? Another question: Do you know about how to convert an implication into a logical statement about in terms of A, B and NOT, AND, OR etc ? So if A implies B then we mean that if A is true then B must be true. If A is false then nothing is being stated about B. So B is either true or false for the implication to still be acceptable. (A implies B) is considered true if and only if ((A and B are true) OR (A is false)) If A is true and B is false then (A implies B) is considered false. So I think it results in: (B) OR (NOT A) as the output of the predicate P(A implies B) (If you are revising for an exam then for goodness sake do some practice questions on this and whatever else you are supposed to learn.) (I only know a bit of degree style logic so please double check me on the things in this post I have already corrected about 10 errors that I have made.) Last edited by SteveB (20130520 06:38:35) #3 20130520 07:54:39
Re: Mathematical Logic and Structures, URGENT!
Let us first substitute ((NOT A) OR B) which I hope means the same as ¬ A v B into x. Last edited by SteveB (20130521 00:28:36) #4 20130521 02:28:31
Re: Mathematical Logic and Structures, URGENT!tHANK YOU GUYS, SOMEONE KNOW: 2  Describe the free object over a given set X on the constant Pos (of partially ordened sets and isotone maps) 