Michael Joyce
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 Oct 12 reviewed Close Let R be the following relation on the set of pairs of integers: Oct 12 awarded Nice Answer Oct 8 comment Game Theory Rulerette, Sprague-Grundy Theorem It would help to clarify the rules of the game further, since I assume most people are not familiar with Ruler. Oct 2 answered Recursive Proof relating to Catalan Numbers Oct 1 answered How did Feynman do this approximation $\sqrt{A^2 + \mu^2\varepsilon^2} =A\biggl( 1+\frac{1}{2}\,\frac{\mu^2\varepsilon ^2}{A^2}\biggr)$? Oct 1 comment Why $(x^3-8)/(x-2)$ is not defined at $x=2$?? I'm a mathematician who would not say that $g$ is defined at $2$. Sep 20 answered Example where $x^2 = e$ has more than two solutions in a group Sep 16 comment Path independence for complex integrals Crazy idea, but you could just summarize the content of the theorem when you refer to it. Sep 12 answered Describing Region in the Complex Plane Sep 7 comment Does orbit-stabilizer theorem holds for monoid action? What's your definition of an orbit of a monoid action? If you define $\text{orb}(x) := \{ m \cdot x : m \in M \}$, then note that you can have $y = m \cdot x$ and $\text{orb}(y) \subsetneq \text{orb}(x)$. For example, $M = \mathbb{N}$ acts on $X = \mathbb{Z}$ via $m \cdot x = m + x$. Then $\text{orb}(x) = \{ y \in \mathbb{Z} : y \geq x \}$. Sep 1 answered Can $AB-BA=I$ hold if both $A$ and $B$ are operators on an infinitely-dimensional vector space over $\mathbb C$? Aug 4 revised Material in a first course in algebraic geometry? deleted 9 characters in body May 16 comment Exercise 1.2 in Hartshorne Chapter I $-$ w $+$ rt. May 10 answered Strongly convex cones May 4 comment Surface Integral, Stokes Theorem, Divergence theorem Sorry, yes according to your terminology, the above comment was an interpretation of an integral with respect to surface area. It refers to a surface $S$ in 3-dimensional space. May 4 comment Surface Integral, Stokes Theorem, Divergence theorem The surface integral $\iint_S f(x,y,z) \, dS$ gives the total mass on a 2-dimensional surface $S$ if the mass density (per unit area) at the point $(x,y,z)$ on $S$ is given by $f(x,y,z)$. Apr 28 comment Union of the two coordinate axes in $\mathbb{R^2}$ - From the book '' Differential Topology '' of Guillemin and Pollack In general, it is better to respond with a comment to an answer rather ask a question about an answer in a different answer. But I'm glad from your other answer that you've figured the problem out. Apr 28 revised Union of the two coordinate axes in $\mathbb{R^2}$ - From the book '' Differential Topology '' of Guillemin and Pollack added 7 characters in body Apr 28 answered Union of the two coordinate axes in $\mathbb{R^2}$ - From the book '' Differential Topology '' of Guillemin and Pollack Apr 23 comment Blow-up toric varieties. I think your suggestions are great, but, at least for #1, it may be better to start with affine space rather than projective space, depending on the sophistication level of the audience.