Mathemanic

### Questions (82)

 13 What is A Set Raised to the 0 Power? (In Relation to the Definition of a Nullary Operation) 11 Generalizing limits of sums, products, and quotients of sequences to abstract topological spaces? 10 Prove $x^n$ is not uniformly convergent 9 Sigma-Algebra: Is it an Algebra, Field, or Something Else? 8 The Matrix in ZFC: A Set-Theoretic Foundation of Matrices?

### Reputation (2,427)

 +20 Prove $x^n$ is not uniformly convergent +10 Matrix Decompositions: Difference between Cholesky Decomposition, Eigendecomposition and Jordan Normal Form Decomposition +10 Area of Triangle when 2 Sides and No Angle Known +10 The Matrix in ZFC: A Set-Theoretic Foundation of Matrices?

 4 Four complex numbers $z_1,z_2,z_3,z_4$ lie on a generalized circle if and only if they have a real cross ratio $[z_1,z_2,z_3,z_4]\in\mathbb{R}$ 4 Why get the sum of squares instead of the sum of absolute values? 4 How do you solve this fraction? 3 Suppose all partial derivatives of $f$ exist at $x_0$; is $f$ continuous at $x_0$? 2 How to prove $f(n)=\lceil\frac{n}{2}\rceil$ is one-to-one and onto?

### Tags (118)

 6 complex-analysis × 24 4 statistics × 4 6 regression × 10 4 arithmetic × 3 4 derivatives × 10 4 circles × 2 4 complex-numbers × 8 4 fractions 4 conformal-geometry × 4 3 matrices × 12