Recent content by konthelion

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    What is the probability of getting a score between 2 and 4?

    What you are trying to find is the cumulative distribution function (cdf) which is defined by: P(X \leq x) = \sum_{y \leq x} p(y) To use different numbers... say you want to find P(X \leq 2) , it would be P(X \leq 2) = p(0) + p(2) =... but P(X < 2) = p(0) \neq p(0) + p(2) = P(X \leq...
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    Can a Sylow Subgroup be Contained in a Sylow p-Subgroup?

    If p is a prime where the order of G is 2p, then G has a normal subgroup, J, with order p (if p is not equal to 2). Since J is normal, then it is contained in the intersection of all Sylow p-subgroups in G (I thought this was by definition... I don't know). Thus, it must be contained in at...
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    Is the Alternating Square Series Sum from 1 to 10201 Solvable?

    Do you see a pattern between the numbers? Try to write it in summation form i.e. \sum_{i=1}^n \left\{... \right\}; after you see the pattern, you should know what n is. Then you can find the sum.
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    Sine laws with Oblique Triangles: The Tower of Pisa

    The "slant height" of a triangle is the height of one of its sloping sides, in this case the side where the leaning tower of pizza is leaning towards. So, yes the length of the slant is the "slant height". The height of the leaning tower would be different (which was what you thought it was).
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    How Can Intersection of Indexed Family Sets Belong to Their Power Sets?

    Let \left\{ A_{i} \right\}_{i \in I} be your indexed set of family. Do you mean this \bigcap_{i=1} A_i = \left\{ x : \forall i \in I: x \in A_i \right\} ?
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    Integrating Factor for Exact Differential Equation

    What did you get for \frac{N_{x}(x,y) - M_{y}(x,y)}{M(x,y)}? If your integrating factor say, \mu is a function of x only, then \frac{d \mu}{dx} = \frac{N_{x}(x,y) - M_{y}(x,y)}{M(x,y)} \mu From here you can solve for the exact equation after multiply the integrating factor by the...
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    Using Trace to Determine Orthogonality of Matrices

    Since tr(AB) = tr(BA) (sorry wrong terminology), so just apply the definition of an orthogonal matrix.
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    How to prove a set is unbounded

    If you think that it is false, you can provide a counterexample. So, if f : [a, b] \to R and let A = [a, b] is bounded, is it necessarily true that f(A) is bounded?
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    Show that the triangle is a right triangle

    You need to show your work. But for starters, one way that you can approach this problem is to solve for "A+B" in both equations in terms of "C". Then you can solve for "C" using these two equations. Last, solve for A and B.
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    Linear algebra - gaussian elimination

    You made a mistake here, this should be -7.
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    When Does A \ (A \ B) Equal B in Set Theory?

    A\(A\ B) = B For A\B, Let x \in A \wedge x \notin B Then, A \ (A \ B) implies that x \in A \wedge (x \notin A \vee x \in B) by DeMorgan's Law Then, by associative law, (x \in A \wedge x \notin A) \vee ( x \in A \wedge x \in B) \implies ( x \in A \vee x \in B) So, A \cup B = B if...
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    Techniques of integration, Partial Fractions problem.

    You have a typo. It's a 3 not a 2. \int \frac{2t}{ (t-3)^2}dt =\int \frac{2}{t-3}dt + \int \frac{6}{(t-3)^2}dt Also, you did not integrate the right term correctly, it's a degree of "-2" not "-1"
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    Integration by parts I believe

    cos2x = 2cos^2x-1 = 1-2sin^2x=cos^2x-sin^2x I believe you mean sin^2x = 1 - cos^2 x?
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    Techniques of integration, Partial Fractions problem.

    You should get A = 2 and B - 3A = 0