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Sign up to join this community Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top Home Questions Tags Users Unanswered Explore our Questions Ask Question real-analysis calculus linear-algebra probability abstract-algebra integration sequences-and-series combinatorics general-topology matrices more tags Interesting 59 Bountied Hot Week Month 0 votes 0 answers 3 views Mayer-Vietoris sequence to find first homology for the double cover of complement of trefoil knot algebraic-topology covering-spaces knot-theory asked 2 mins ago Adam Martens 1,783 0 votes 0 answers 6 views Solve the differential equation: $y`+ \frac{y} {sinx} =tg\frac{1}{2}x$ ordinary-differential-equations asked 2 mins ago mona1lisa 165 0 votes 0 answers 7 views Determine for which values λ ∈ R the integral $\int x^λ lnx \, dx$ converges calculus integration lambda-calculus modified 16 secs ago studentlovescalc 1 0 votes 2 answers 42 views Conceptual question about assuming the existence of a function in order to prove the existence of another function functions elementary-set-theory modified 5 mins ago Ray LittleRock 1,777 1 vote 1 answer 10 views Show that : $ \sup_{x\in \overline{\text{co}} (A)}\|x\|=\sup_{x\in A} \|x\| $ analysis banach-spaces answered 5 mins ago Olof 1,066 0 votes 2 answers 16 views Easy way to show continuity continuity modified 5 mins ago Azif00 7,308 0 votes 1 answer 12 views Jordan measure of a ball real-analysis measure-theory modified 6 mins ago copper.hat 140k 0 votes 0 answers 11 views Calculation of Residues with non-removable singularities residue-calculus modified 6 mins ago Sharat V Chandrasekhar 912 0 votes 0 answers 4 views Are finite abelian groups isomorphic to k-character groups for arbitrary alg.closed k? representation-theory characters asked 7 mins ago Daniel Santiago 1 0 votes 1 answer 43 views Prove that $ \sum \limits_{n=1}^{\infty} \frac{n}{(n+1)^{(n+2)} (n+2)!}(-1)^{(n+1)} = \frac{23}{24} - \frac 2 3 \sqrt 2 $ real-analysis linear-algebra sequences-and-series taylor-expansion answered 8 mins ago WhatsUp 7,441 0 votes 0 answers 4 views fourier series representation of a square wave inverter waveform fourier-series even-and-odd-functions asked 10 mins ago PcumP_Ravenclaw 63 0 votes 0 answers 18 views Infinitely many primes $p=6r-1$ such that $(k,r) = 1$. elementary-number-theory modified 12 mins ago Matt Samuel 48.2k 0 votes 0 answers 4 views Nash equilibrium and score game-theory nash-equilibrium asked 12 mins ago basket 1,937 1 vote 1 answer 22 views Prove $\cos(\pi x)=\sinh(\pi)/\pi\sum_{n=0}^{\infty}\left(\frac{\left(-1\right)^{n}}{1+\left(x-n\right)^{2}}+…\right)$ sequences-and-series trigonometry answered 13 mins ago user 11.4k 1 vote 1 answer 11 views Complex integration over contour by definition complex-analysis answered 1 min ago Olof 1,066 -1 votes 2 answers 23 views Evaluate the flux of $\operatorname{curl}\mathbf F$ through the given surface. multivariable-calculus stokes-theorem modified 16 mins ago user170231 6,875 1 vote 1 answer 751 views Are all integrals of closed contours over an analytic path = $0$? 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