Sep
28
reviewed Looks OK Representable functors, why are they important?
Sep
28
reviewed Approve suggested edit on General solution to first-order ODE in 3D
Sep
28
reviewed Leave Closed How to construct a smooth curve whose range is dense in $\mathbb R^2$?
Sep
28
reviewed Close Is the function $\sin(\lvert x\rvert)$ differentiable?
Sep
28
reviewed Close $V=\min \{X,Y\}$ is independent of $W=|X-Y|$
Sep
28
reviewed Close First order separable differential equations
Sep
28
reviewed Leave Open how inner products are defined on a vector space?
Sep
28
reviewed Close Let $V$ be finite dimensional v.s. and $0 \ne T\in \mathscr L(V)$ , then $\exists$ $S \in \mathscr L(V)$ such that $0 \ne T \circ S$ is idempotent
Sep
28
reviewed Reopen What number is “b” in the following theorem?
Sep
28
reviewed Close Is sin(1/x) periodic?with what period time?
Sep
28
reviewed Close The limit of $\sqrt{x^2+x+1}-\sqrt{x^2+1}$ as $x\to\infty$
Sep
28
reviewed Leave Open Separate a list of spheres into several lists, each contained in a sphere with a radius no larger than specified.
Sep
28
reviewed Close Non-discrete locally compact Hausdorff groups which do not satisfy the second axiom of countability
Sep
28
reviewed Approve suggested edit on How do I test if a set of matrices is a subspace?
Sep
27
awarded  Popular Question
Sep
25
reviewed Reopen Calculate arc length of a logarithmic spiral between two points.
Sep
25
reviewed No Action Needed How the gradient vector is in the direction of maximum increase of function and its magnitude is the maximum increase?
Sep
25
reviewed Close Trigonometric identity
Sep
25
reviewed Approve suggested edit on Calculate arc length of a logarithmic spiral between two points.
Sep
24
reviewed Close Linear Algebra Book