Nov 11, 2018 · The Integration by Parts formula may be stated as: $$\\int uv' = uv - \\int u'v.$$ I wonder if anyone has a clever mnemonic for the above formula. What I often do is to derive it from the Product R...

Oct 8, 2012 · U(N) and SO(N) are quite important groups in physics. I thought I would find this with an easy google search. Apparently NOT! What is the Lie algebra and Lie bracket of the two groups?

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Jan 5, 2016 · This is a sort of addendum to Qiaochu's answer, the purpose of which is to tie up the loose end it leaves in the sense that it only considers isomorphisms compatible with the short exact sequence associated to the surjective det: U(n) → S1. Claim: Any group homorphism ψ: SU(n) × S1 → U(n) must form part of a commutative diagram 1 → SU(n) ι1 → SU(n) × S1 π2 → S1 → 1 θ↓ ψ↓ ...

Oct 2, 2011 · I need to graph a rectangle on the Cartesian coordinate system. Is there an equation for a rectangle? I can't find it anywhere.

Jan 20, 2015 · I'm trying to proof the following isomorphism U(n) ≃ SU(n) × U(1) Zn

Jan 29, 2015 · Wikipedia states: "The unitary group U(n) U (n) is a real Lie group of dimension n2 n 2. " There seem to be two typos: one, unitary matrices are complex. So it should be a statement about complex Lie group. The other typo is n2 n 2: n2 n 2 is the dimension of GLn G L n and U(n) U (n) is a proper subgroup so clearly its dimension must be smaller than n2 n 2. What's the dimension of U(n) U (n)?

I was playing with my calculator when I tried 1.5! 1.5!. It came out to be 1.32934038817 1.32934038817. Now my question is that isn't factorial for natural numbers only? Like 2! 2! is 2 × 1 2 × 1, but how do we express 1.5! 1.5! like this?

May 9, 2016 · Prove that the sequence $\\{1, 11, 111, 1111, .\\ldots\\}$ will contain two numbers whose difference is a multiple of $2017$. I have been computing some of the immediate multiples of $2017$ to see how

This endomorphism ring is simply Zn, since the endomorphism is completely determined by its action on a generator, and a generator can go to any element of Zn. Therefore, the automorphism group Aut(Zn) is the group of units in Zn, which is Un = U(Zn).