Recent content by sapiental

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    Matrix relation of sets. symmetric, antisymmetric,reflexive,transitive

    Hey, thanks for the reply! I didn't put parenthesis around the ordered pairs (a,a),(b,b),(c,c) for the first problem, sorry. I don't think it's transitive since we have (c,b) and (b,a), and it doesn't contain (c,a). How does that sound? Thanks
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    Matrix relation of sets. symmetric, antisymmetric,reflexive,transitive

    Homework Statement relation A = {a,b,c} for the following matrix [1,0,0;1,1,0;0,1,1] is it reflexive, transitive, symmetric, antisymmetric Homework Equations ordered pairs. The Attempt at a Solution i wrote the ordered pairs as (a,a),(b,a),(b,b),(c,b),(c,c) I only that...
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    Counting Problem: Inviting Jack's Friends to Dinner

    the problem states "assuming 10 friends consist of 6 single people and 2 married couples" sorry for not clarifying. would it still be off?
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    Counting Problem: Inviting Jack's Friends to Dinner

    for c I did out all the cases case 1. where no married couples are invited, we have 6 friends for 5 spots = 6 different ways to invite case 2 one of the married couples for 2 spots, 6 singles for (6,3) = 20 different ways. since there are 2 married couples I multiply by 2 for a total...
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    Counting Problem: Inviting Jack's Friends to Dinner

    Hi, thanks for all the input it really helped me gain more insight into the problem My new approach does not depend on the order and I employed the permutation and combination method. For a) I did C(10,5) = 10!/[(5!)(5!)] and got 252 possible combinations for b) i did the following C(2,1)...
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    Counting Problem: Inviting Jack's Friends to Dinner

    Homework Statement a) if jack has 10 friends, in how many ways can he invite 5 of them to dinner. b) suppose 2 friends don't like each other, and if one is invited, the other can't come. c) what if 2 of the friends are married and if they invite that friend, the spouse must come. Homework...
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    Express t and s as functions of x and y given

    Homework Statement How do I express t and s as functions of x and y given x = -(2t+1)*s/(t^2-1) y = e^(t + ln|s|) I keep getting stuck in a loop. Homework Equations substitution The Attempt at a Solution x= -(2t+1)*s/(t^2-1) I get t = sqrt(1-s/x) t = sqrt(1-s/x) s = e^(-t)y...
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    Calculating Double Sum: (n=3)(i=0)∑(n=2)(j=0)∑(3i+2j)

    Homework Statement Compute the following double sum (n=3)(i=0)\sum(n=2)(j=0)\sum(3i+2j) Homework Equations sums The Attempt at a Solution my answer follows expanding the first sum, then just doing the last one i get (n=3)(i=0)[tex]\sum[tex](6+9i) = 78 thanks!
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    Inverse of Function f: R -> R Defined by f(x) = x^3+1

    Homework Statement f: R -> R defined by f(x) = x^3 + 1 a) determine if it is one to one b)find its inverse c) calculate (f o f) Homework Equations if f(x) is one to one, if a = b, f(a) = f(b) The Attempt at a Solution a) yes it is because a^3 + 1 can't equal to b^3 +...
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    How do you compute A - B, B x C, AB, and A(B-A) for given sets?

    Homework Statement Let A = {1,3,5,6}, B = {3,5} and C = {a,b,c} Compute a. A - B b. B x C (cartesian product) c. AB d. A(B-A) Homework Equations Table of set computation in text The Attempt at a Solution a. = {1,6} b. =...
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    Introduction to the product rule

    Homework Statement a) How many bit strings are there of length 8? b) How many bit strings are there of length 8 which begins with 2 1's? Homework Equations Product Rule The Attempt at a Solution a) Since a bit string is either 0 or 1 there are two possibilities for each one...
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    Proving: If n Divisible by 3, Then n^3 Divisible by 3

    Homework Statement Prove the following: If the integer n is divisible by 3 then n^3 is divisible by 3. Homework Equations Direct Proof The Attempt at a Solution n = 3m n^2 = 9m^2 n^2 = 3(3m^2) I think the proof is done at this point because the 3 factors out but I also...
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    Negation of All Participants Being IT and Math Majors: Using Basic Logic Laws

    Homework Statement Use logic to write the negation of the sentence: All participants of this course are IT majors and are Math majors (be careful, use basic logic laws) Homework Equations DeMorgan's Law The Attempt at a Solution Letting P(x) be Participants who are IT majors...
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    Confirming Wronskian Determinants with Basic Functions

    Homework Statement Hi, could someone please confirm my results. I just put my answers because the procedure is so long. let me know if you get the same results. 1) Wronskian(e^x, e^-x, sinh(x)) = 0 2) Wronskian(cos(ln(x)), sin(ln(x)) = 1/x * [cos^2(ln(x)) + sin^2(ln(x))] = 1/x thanks in...
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