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  1. K

    Anyone know prolog?

    Does anyone here know Prolog? I'm using the SWI-Prolog interpreter. Given this list: [[1, 2], [2, 3], [3, 4]] how do you make it say Yes if 2 (of the first list) = 2 (of second list) and 3 (of second list) = 3 (of third list)? I'm having trouble visualizing this fact as the elements in the...
  2. K

    Java How do display/generate webpage content with info from an array in a .java file?

    Does anyone know how I would go about displaying/generating webpage content with info from an array in a .java file? Suppose you click on cars.com, once you do, the webpage will display the contents (say car names) of an array from a .java file. How do I do this? Thanks.
  3. K

    Context-free grammar: derivations and ambiguity

    I have a question regarding about CFGs, derivations, and ambiguity. Say you are given some CFG that produces A, B, or C You are able to come up with two different derivations for A To say the CFG that produces A, B, or C is ambiguous, you must find two different parse trees for some...
  4. K

    Simplifying regular expression?

    Does anyone know if this regular expression can be simplified? (a*bc*bc*|c*)*b I tried (a|b|c)*b, but it's not correct.
  5. K

    XQuery XML help

    I have to write an XQuery that for example, "returns a list of books for a given author". The "given author" in this case can be anything. Therefore, I was wondering what do I need to add to give the query someting, which in return, it will process it. For example, for $x in...
  6. K

    Minimum closure of F (functional dependencies) help

    Homework Statement F = {S -> NOPQZVWX, NX -> UV, NXT -> RY, YQ -> NXR, QZ -> S, PQ -> S} Find the minimum closure of F. Homework Equations none The Attempt at a Solution So far I have made RHS of each FD into a single attribute and then I eliminated redundant attributes from...
  7. K

    Help Joining Two Tables in SQL?

    I'm having trouble getting the following work. Can anyone help me? I have two tables that look like the following: Table 1 Table 2 A B A B C 1 4 1 4 6 2 5 3 6 How do I join both of them such...
  8. K

    Big-O and big-omega question

    Hi, I am a bit confused here. Just say you're given code and it says to show the best-case analysis and the worst-case analysis. When you show the best-case, what should the answer be in? In big-O or big-omega? Similarly, if you show the worst-case, what should the answer be in? big-O or...
  9. K

    Dijkstra's algorithm proof?

    Does anyone here know how to prove this? I'm stuck on how to even get this started. Let G be a connected, weighted and undirected graph where all edges have a weight of 1. Prove that if Dijkstra's algorithm is run on this graph, G, then the tree returned is a breadth-first tree.
  10. K

    Finding a constant for a partial differential equation

    Can anyone help me with this question? I tried taking the derivative of u with respect to x and then summed the third derivative, but I'm getting nowhere. Any help would be great, thanks. Let u(x1, x2, … , xn) = http://img480.imageshack.us/img480/1694/image0027hm.gif [Broken],[/URL] where a...
  11. K

    Computer science proving big-O definition

    I have two questions here. I must prove that f(n) = 100n^2 + 5n + 10 is in big-O of g(n) = n^3 - 100n^2 I already found a constant c and an n that satisfies the condition such that f(n) \leq c * g(n). Let c = 1 and n = 201. However, I am stuck on showing/manipulating the algebra that this is...
  12. K

    Showing a set is bounded

    Q: Show that every bounded set in R has a least upper bound. Using either "Every monotonic and bounded sequence is convergent" or "Every bounded sequence has an accumulation point" or "Every bounded sequence has a convergent subsequence" I'm not really sure how to start this out, but would...
  13. K

    Converting 29 and 0.7 to IEEE single precision floating point

    I am having difficulty in converting 29 and 0.7 to IEEE single precision floating point. For 29, I represent 29 as a product of a power of 2 using 58/4 * 21. However, I am having trouble getting the mantissa value because 58/4 is 14.5, and I need something in the format of 1.[numbers]. Any...
  14. K

    Summation of n^2k. k = 1 to infinity

    Is the summation of k = 1 to infinity for n2k equal to n2 / (1 - n2)?
  15. K

    Mathematica Mathematical induction question?

    Q: When a binary number is incremented by 1, there may be a carry that may carry over several bit positions i.e. 1010111 is incremented and the carry distance is 3. Given a natural number n, find the average carry distance when incrementing a binary number b in the inverval 2n <=b <= 2n+1...
  16. K

    Determining max and min pts of a polar curve

    Determine the maximum and minimum values of the curvature at points of the polar curve r = 3 + sin q. I know that the polar curve, r = 3 + sin q is sort of similar to an upside down heart when graphed. However, I am not sure what to do when finding the maximum and minimum values of the...
  17. K

    Antiderivative of the following function

    How would you guys come about getting the antiderivative for the following function? 8u^5 / ((4 + u^4)^2) I tried rearranging the equation like the following: 8u^5 * ((4 + u^4)^(-2)), but it's not really getting me anywhere. I tried to do a u substitution, but can't find one where it...
  18. K

    What property to look for to see if a matrix is diagonalizable?

    Hi, Just say you are given a 3x3 matrix with a value k in it. What would be the best way to find out if it is diagonalizable or not for certain values of k? The matrix in question is -1 0 0 k 1 0 -2 1 -1
  19. K

    Determinant proof

    Is this proof correct? Show that det(A + B^T) = det(A^T + B) det(A + B^T) = det(A^T + B) det(A) + det(B^T) = det(A^T) + det(B) det(A) + det(B) = det(A) + det(B) Thanks.
  20. K

    Determinants and Matrix Inverses Proofs

    Can anyone help me start this out? I got absolutely no clue. Q: If A and B are n x n matrices, AB = -BA, and n is odd, show that either A or B has no inverse. I know that we have to show that either det A is 0 or det B is 0, but I have no clue how to show it with the given information...
  21. K

    Another linear transformation question

    Q: In each case, show that T is not a linear transformation. T[x y]^T = [0 y^2]^T A: If X = [0 1]^T then T(2X) = [0 4]^T while 2T(X) = [0 2]^T I don't quite understand this solution. What are we trying to accomplish here? So, since T(2X) = [0 4]^T while 2T(X) = [0 2]^T do not yeild...
  22. K

    Inverse of a Linear Transformation

    Hi, Is there a formula to do this? The textbook just says to "reverse" the action of T to get T^-1 (T inverse). Can someone explain to me in laymen terms, how to accomplish this? For example, For T = [2x y]^T is T^-1 = [-2x y]^T?
  23. K

    Rank of a matrix proof

    Q: If A is an m x n matrix and rank A = m, show that m <= n. I know that by definition if A is m x n, then rank A <= m and rank A <= n. However, I do not know how I would do this if rank A = m. Any help would be great thanks.
  24. K

    Subspaces R^n

    Q: Determine whether U is a subspace of R^3. U = {[0 s t]^T | s and t in R} A: Yes. U = span {[0 1 0]^T, [0 0 1]} Can someone explain to me how the heck they come up with that answer? Seems so random.
  25. K

    Probability density function

    How do I calculate the PDF of someone's earning followed by their mean and variance? This is the question: Given density function f(x) = 2.5 if 0.1 < x < 0.5 0 otherwise The person is paid by the # of jobs they finish rather than by the hour. They get 10$/job. Calculate...
  26. K

    Binomial Distrinution - is my answer reasonable?

    Q: The simplest error detection scheme used in data communication is parity-checking. Messages sent consists of characters, each character consisting of a number of bits, 0 or 1. In parity checking, a 0 or a 1 is appended to the end to make the number of 1's even. The receiver checks the number...
  27. K

    Linear algebra and vectors. confused

    Let P1 = P1(2, 1, -2) and P2 = P2(1, -2, 0). Find the coordinates of P, which is 1/4 the way from P2 to P1. The answer is P = P(5/4, -5/4, -1/2) Can someone explain to me the concept of this? I don't quite understand it. So basically we are suppose to find a vector P that is 1/4 away from...
  28. K

    Probability mass function of a hash table?

    A hash table is a storage structure that calculates the storage address from a record key, k where f1(k) returns the storage address. Sometimes the hash function returns the same address for several keys (called collision). To fix this problem, a scheme called secondary hashing uses a sequence...
  29. K

    Poisson Process Probability Question Help

    I'm having a bit of trouble in coming up with the solution for this question A hard disk manufacturing process desposites a thin coating of magnetic material on a plastic substrate. Empirical measurement has shown that the process introduces 20 defects per 15000cm squared. A disk pack...
  30. K

    Algebraic manipulation of identity matrix

    I was doing a few practice questions and was a bit confused about how the solution manual manipulated the I identity matrix. For example, Just say you had the following I - 2A = B where A and B are 2x2 matrices. B is given, but we need to find A. Therefore, shouldn't it be -2A =...
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