Recent content by xpoferens

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    Studying Studying Math without propper foundations

    I think I have all 4 criteria minus discipline, but I that I can learn.. I've been asking around (friends, family, physicsforums) and everyone has been giving me these positive replies, so I think I'm going to do it despite my lack of confidence. I have nothing to lose. Thanks for advice :)
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    Studying Studying Math without propper foundations

    I'm 19 years old and I am in first year computer science. I've really fallen in love with the math that we do (discrete math, linear algebra, multivariable calculus) in this program and I'm thinking of switching majors to math or do a double major in math and computer science.. What I'm...
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    Intersections and Unions of powersets confusing

    OK I actually just thought that since it's easier to prove that something is false I used a counter example. Consider A = {1} and B = {2} In this case P(A) U P (B) does not contain {1, 2} but P(A U B) does. That seems logical to me..
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    Intersections and Unions of powersets confusing

    Ok thanks alot, Now for part b, after thinking about it I can intuitively see why the equality is false but I don't know how to prove it. Could you point me in the right direction please?
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    Intersections and Unions of powersets confusing

    ok so if x is an element of P(A inter B) then a is a subset of (A inter B) so a is a subset of A AND a is a subset of B so a is an element of P(A) AND a is an element of P(B) therefore a is an element of P(A) inter P(B). Is that reasoning sound?
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    Intersections and Unions of powersets confusing

    Homework Statement let A and B be finite sets Let P(A) denote the Power Set of A (set of all subsets of A)Homework Equations Prove or disprove: a) P(A inter B) = P(A) inter P(B) b) P(A U B) = P(B) U P(B) The Attempt at a Solution So I tried drawing Venn diagrams and came to the conclusion...
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    Is this function injective, surjective, or both?

    OK nevermind i figured it out. Is there a way to remove my original post? Or should I post my reasoning incase it could be helpful to others?
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    Is this function injective, surjective, or both?

    Homework Statement The following function f is a function from R to R. Determine whether f is injective (one-to-one), surjective (onto), or both. Please give reasons. Homework Equations f(x) = (x+1)/(x+2) if x != -2 f(x) = 1 when x = 2 The Attempt at a Solution f'(x) = 1/(x+2)2...
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