Recent content by adityab88

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    Graduate An open mapping is not necessarily a closed mapping in functional analysis

    Firstly, I strongly suggest you study topology. You won't be able to understand such concepts without knowledge of that course, and it is a crucial course in your study of mathematics. Just read any introductory book. Your question is very basic (I think it will also be answered in a standard...
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    Graduate Proving the Properties of Subspace U⊥ in Rn | Help with Subspace Concepts

    Let u,v be in U⊥. Let k be a constant in R. Now <u,w>=0 for all w in U and <v,w>=0 for all w in U. Thus by linearity of inner product we have <u+kv,w>=0 for all w in U. Thus, u+kv is also in U⊥ for all u,v,k. Thus U⊥ is a subspace. For the second part, DIY but here are some hints: - We...
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    Graduate An open mapping is not necessarily a closed mapping in functional analysis

    We know that a linear operator T:X\rightarrowY between two Banach Spaces X and Y is an open mapping if T is surjective. Here open mapping means that T sends open subsets of X to open subsets of Y. Prove that if T is an open mapping between two Banach Spaces then it is not necessarily a closed...
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    Graduate A Question to Trouble Even the Best of You

    good stuff good stuff how long did it take you to "experiment" and find the final sequence? cause i was looking for it, too, but my experimentation did not really work.
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    Graduate A Question to Trouble Even the Best of You

    hello ... ppl i am quite sure you do not need programming equipment. just your brains will suffice; i am sure of this because i saw this question on a maths paper, where computers were not allowedthis is all i have: the difference between the consecutive primes has to be a multiple of 30, i have...
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    Graduate Greatest Lower Bound: Prove It!

    dedekind cuts/ cauchy sequences precisely. dedekind cuts or even cauchy sequences can be used prove such a statement.
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    Undergrad Can Divisibility of Powers Imply Divisibility of Bases?

    just read a number theory book i am sorry in that i did not mean it to come that way. all i mean is that an answer to such a question is pretty standard and can be found in almost any number theory textbook. people can just read up the solutions. i did not mean to humiliate ppl. sorry...
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    Graduate Greatest Lower Bound: Prove It!

    this is not number theory this is not number theory, but it is instead mathematical analysis. it is a very basic result that has been used to construct the real numbers and i think you will find it in any standard intro to analysis textbook (i personally recommend principles of mathematical...
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    Graduate A Question to Trouble Even the Best of You

    Find the smallest possible arithmetic sequence consisting of seven primes. For example, the smallest possible arithmetic sequence consisting of five primes is: 5, 11, 17, 23, 29. By the way, by "smallest possible" I mean that the last term in the sequence must be the smallest possible of...
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    Undergrad Can Divisibility of Powers Imply Divisibility of Bases?

    it's quite easy prove by contradiction i am very suprised that such an EASY question has stumbled so many of you people. you should be ashamed of yourselves