Recent content by Goldenwind

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    How to solve equations with mod?

    I've looked up plenty of sites, but all of the things are far, far above my comprehension. I guess what I'm (potentially stupidly) expecting is something like: "a mod b = 1" --> "(a + 1) / b = 0", or: "x / y" --> "x * (1/y)" Something I can use to isolate x such that I may continue my coding...
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    How to solve equations with mod?

    Solving equations with "mod" Homework Statement I have a homework problem. I'm in computer science, however one of my programs requires me to solve this equation. I'm afraid it's beyond my expertise. (a * x) mod b = 1 This needs to be rearranged in the form of x = ... Due to the existence...
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    The limit as x approaches infinity

    Homework Statement (3x-2) / (9x+7) As x approaches infinity. The Attempt at a Solution I know the procedure, but am then stuck: - Rearrange - Plug in infinity for x - Evaluate Tried breaking it into 3x / (9x+7) - 2 / (9x+7) The second thing would go to zero. The first, no...
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    What Does A (+) B Represent in Set Theory?

    Found it. For anyone else with a similar problem, it's the "symmetric difference" A (+) B = AuB - AnB (The set of elements in either A or B, but not in both)
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    What Does A (+) B Represent in Set Theory?

    [SOLVED] Quick, simple question on sets Homework Statement A - B is the difference A u B is the union A n B is the intersection A (+) B is what? I would google this, but I haven't a clue what the symbol or function is called. It's supposed to be a +, inside a circle. Can someone...
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    Solving the Mystery of dl in Integrals

    I'm trying to deal a problem using this formula, but I'm unclear as to what dl represents (Or if it is the same as dx in most integrals, then in that case I don't know what the lowercase L is) {\cal{E}} = \int_{a}^{b} \vec{E} \cdot \vec{dl}
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    Solution by Iteration: Nonrecursive Formula for a_n = 2(n+1)^n

    Yeah, I see my mistake... when I replaced n with n-1, or n-1 with n-2, I didn't change the (n+1) at all. Doing so would lead to the factorial, instead of (n+1)^n. Thank you for your help :)
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    Solution by Iteration: Nonrecursive Formula for a_n = 2(n+1)^n

    a_n = 2(n+1)! ...is what it looks like to me. However, even if I know the formula, I need to demonstrate that this *is* the formula, via iteration. As in, I start out with a_n = (n+1)a_{n-1}, then replace a_{n-1} with a_{n-1} = (n+1)a_{n-2}, then replace a_{n-2} with a_{n-2} = (n+1)a_{n-3}...
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    How to handle aboslute values in integrals

    Remember that a definite integral is a measure of area under a curve. If you look at x^3 from -a to a, the total area would be 0, as due to the symmetry, the positive and negative areas cancel out. But what if we had |x|^3? Then it'd look the same, except all negative values would be flipped...
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    Money Dealing Strategies - Find Recurrence Relation

    Homework Statement A country uses as currency coins with values of 1 peso, 2 pesos, 5 pesos, and 10 pesos and bills with values of 5 pesos, 10 pesos, 20 pesos, 50 pesos, and 100 pesos. Find a recurrence relation for the number of ways to pay a bill of n pesos if the order in which the coins...
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    Solution by Iteration: Nonrecursive Formula for a_n = 2(n+1)^n

    a_n = (n+1)a_{n-1} Which is the same as \frac{a_{n+1}}{n+1} = a_{n}\frac{a_{n+2}}{{(n+1)}^2} = a_{n}\frac{a_{n+3}}{{(n+1)}^3} = a_{n} I still don't see my mistake :( This is pretty much what I did above, only the other way around >.>
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    Solution by Iteration: Nonrecursive Formula for a_n = 2(n+1)^n

    Here's the spreadsheet I'm using to check my answer. First column is n Second column is the recursive Third column is my proposed answer
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    Solution by Iteration: Nonrecursive Formula for a_n = 2(n+1)^n

    [SOLVED] Recurrence Relations Homework Statement I need to express this recursive statement as a nonrecursive formula, using the technique of itteration. a_n = (n+1)a_{n-1} a_0 = 2 The Attempt at a Solution a_n = (n+1)a_{n-1} a_n = (n+1)(n+1)a_{n-2} = (n+1)^{2}a_{n-2} a_n =...
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    Combinatorics problem - Permutations of ABDEFGH

    That's what I figured, hence how I got my answer, but just wanted to check to be sure.
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    Combinatorics problem - Permutations of ABDEFGH

    In theory I'm done this question, but would like to get it checked. 22) How many permutations of the letters ABCDEFGH contain c) the strings BA and FGH? Answer: 5 objects: BA, C, D, E, FGH. Total: 5! = 120 This is following the example in the book. However, the example only has...
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