Recent content by Thorn

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    Graduate What is the meaning of equivalence classes in complex projective space?

    I've been thinking...and am starting to think that I don't understand complex projective space...So, it's defined as ( Cn+1 \{0,0} / C\{0} ). Now, I think this is just the set of planes in 4 space that pass through the origin... and one can consider how they would all intersect a 3 sphere and...
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    Graduate Projective Space: CP1, Homeomorphism to 2-Sphere?

    I have a question about complex projective space... specifically CP1 which can be thought of as the action of C on C^2\{0} which gives rise to the equivalence classes of "lines" passing through the origin in C^2 (but not including the 0) Now, any vector in complex space, when multiplied by the...
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    Graduate Does Convergence in Measure Always Guarantee Almost Uniform Convergence?

    If a sequence of measurable functions (real-valued) converges in measure, is it true that you can find a subsequence that converges almost uniformly? (This is obviously true if m*(domain) is finite...but in general is it?) If so, can someone outline a little why?
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    Graduate Is the product of two open sets open?

    Say we have open sets from two topological spaces. A is an open subset of T1 and B is an open subset of T2. So for these two open sets, A, B. Is A X B open itself? I see this is the case in R x R, where R is the real number line. I am wanting to say that this is just true in general... If so...
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    Graduate Can a Set Be Measurable if Its Measure is Less Than the Sum of Its Parts?

    Ha...well then it seems that EVERY non measurable set would be an example of m*(U Ei) < Σ m*(Ei)..
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    Graduate Can a Set Be Measurable if Its Measure is Less Than the Sum of Its Parts?

    So I take it, then there isn't an example of this...even for non-measurable sets..?
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    Graduate Can a Set Be Measurable if Its Measure is Less Than the Sum of Its Parts?

    yeah... m* is the Lebesgue outer measure. So, you can say things like m*(E) when E isn't even measurable!? I didn't think m would be defined from a non measurable set...
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    Graduate Can a Set Be Measurable if Its Measure is Less Than the Sum of Its Parts?

    I was told that you can find a disjoint sequence of sets...say {Ei} such that m*(U Ei) < Σ m*(Ei).. That is the measure of the union of all these sets is less than the sum of the individual measure of each set... This is obvious if the sets aren't disjoint...But can someone give me an example...
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    Graduate Show G(p) of Order p^t when G is an Abelian Group of Order (p^t)m

    Well...Actually, I could use Cauchy's theorem for Abelian Groups... "If G is a finite abelian group and p is a prime that divides |G|, prove that G contains an element of order p... we know that p divides |G|...and p2 divides the order of G...and so on and so on until we have pt divides...
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    Graduate Show G(p) of Order p^t when G is an Abelian Group of Order (p^t)m

    Geez...I have no idea where to start... Ok, I was looking at a lemma... "Let G be an abelian group and a \in G and is an element of finite order. Then a = a1+a2+...+ak, with ai an element of G(pi), where p1,...,pk are the distinct positive primes that divide the order of a" ... now...
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    Graduate Show G(p) of Order p^t when G is an Abelian Group of Order (p^t)m

    If G is an abelian group of order (p^t)m, and (p,m)=1, show that G(p) has order p^t and G(p) = {a e G| |a|=p^m where m is a natural number} any suggestions?
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    Proving cos^4(x)= 3/8+1/2(cos2x)+1/8(cos4x)

    I told you to watch out for that 2x! ><
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    How Do You Integrate ∫x²e^(-2|ax|) dx with Absolute Values?

    OH YEAH! DONT IGNORE THE ABSOLUTE VALUE...cause e^(-x) is a lot different that e^(x)...do you have limits on that integral?
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    How Do You Integrate ∫x²e^(-2|ax|) dx with Absolute Values?

    Well, yeah...intergrate by parts! and try to reduce x^2! that is write e^(whatever) as the u'...so that when you apply the formula, you actually differentiate x^2...thus making it 2x...then do it again...and make it 2...then you will have nothing more than an integral with e(whatever that...
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    Proving cos^4(x)= 3/8+1/2(cos2x)+1/8(cos4x)

    ha...tell me what you get