Recent content by UOAMCBURGER

  1. U

    Vector space has dimension less than d

    Homework Statement Problem given to me for an assignment in a math course. Haven't learned about roots of unity at all though. Finding this problem super tricky any help would be appreciated. Screenshot of problem below. [/B] Homework Equations Unsure of relevant equations The Attempt at...
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    Convergence: Epsilon-N Definition

    oh yes i do. Update: I used L'Hospital's Rule to find that the sequence converges to 2. But now separating the logarithms you get 2+ln(n^2)/3+ln(n), so would that change my answer I get using L'Hospital's rule? or can i assume an converges to 2 and then use the definition with L = 2?
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    Convergence: Epsilon-N Definition

    Homework Statement Homework Equations epsilon - N definition of convergence [/B]The Attempt at a Solution Not sure how to determine whether this sequence converges or not. Thought it could have something to do with the fact that e^2 and e^3 are just constants, so when n > infinity those e...
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    Projection Matrix Homework: Equations & Solution

    Don't worry, I learned how to solve it now. since you can find the projection matrix pretty easily then you just plug in the values from the given vector, here W (unit vector of v) the squares cancel the square roots and you're left with that matrix in solution P. But i was wondering how do you...
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    Projection Matrix Homework: Equations & Solution

    Homework Statement [/B]Homework EquationsThe Attempt at a Solution The solution is obviously given, but I don't really understand what is done there. What method is being used? so I can understand, because i see how they attained v, but then that vector normalised is not correct is it?
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    Matrix Solutions: Find Linearly Independent Solutions

    Homework Statement given the matrix https://scontent.fhlz2-1.fna.fbcdn.net/v/t1.15752-9/40882602_313421129235428_2500668957757800448_n.png?_nc_cat=0&oh=7f5d6372c263996c6a11969b072d1349&oe=5BF8F2B7 in RREF we see solution to this system is x1+x2+x3 = 0 in the textbook it says which solutions...
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    Is f Injective? Understanding the Composition of Functions

    I think my definition was correct, I meant given two elements in the domain (hence x,y ∈ A) then f(x) != f(y) (meaning that no two elements in A can map to the same element in the codomain, B) .. the definition of injective functions. the x !=y just means that the two elements in the domain...
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    Why Must n Equal 4q or 4q+2 If It Isn't 4q+1 or 4q+3?

    Right, but I don't understand what you mean in post #6. What is clear to me so far is this: For any n ∈ Z, n can be written in the following way, n = x*y + r, where x,y,r ∈ Z also. Now given (in this example) that n != 4q+1 and n != 4q+3, (this is where I'm confused), Why wouldn't it follow...
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    Why Must n Equal 4q or 4q+2 If It Isn't 4q+1 or 4q+3?

    That doesn't really make sense to me. Can any number in Z, (since that is what we are working with), be represented by 4q+x : x,z ∈ Z? Because it is for n ∈ Z.
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    Is f Injective? Understanding the Composition of Functions

    Homework Statement Let A, B, C be finite sets such that A and B have the same number of elements, that is, |A| = |B|. Let f : A → B and g : B → C be functions. (a) Suppose f is one-to-one. Show that f is onto. (b) Suppose g ◦ f is one-to-one. Show that g is one-to-one.Homework EquationsThe...
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    Why Must n Equal 4q or 4q+2 If It Isn't 4q+1 or 4q+3?

    yes i understand that, its just applying De Morgan's laws. But why does that imply that n=4q or n = 4q+2 ONLY? on the answer page it says "since n≠4q+1∧n≠4q+3, it follows that n = 4t or 4t + 2 for some t ∈ Z." My question is why do they say it follows that, that is the case? because how do we...
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    Why Must n Equal 4q or 4q+2 If It Isn't 4q+1 or 4q+3?

    Homework Statement For any integer n, let A(n) be the statement: “If n 2 = 4k + 1 for some k ∈ Z, then n = 4q + 1 or 4q + 3 for some q ∈ Z.” Use proof by contradiction to show that A(n) is true for all n ∈ Z.The Attempt at a Solution [/B] the answer sheet says that since n !=4q+1 and n !=...
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    Proof by Contradiction: Converse of A(n) Holds for All n ∈ Z

    yes its meant to be n2, and obviously I did NOT intentionally write it as n 2 ...
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    Proof by Contradiction: Converse of A(n) Holds for All n ∈ Z

    oh that is why i was getting confused, because given statement A>B for a proof by contradiction you get A>~B and show some contradiction, hence my question about the order of the proof. I see what I've done, thanks.
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