54 True or false? $x^2\ne x\implies x\ne 1$ 43 Coffee Break Riddle 27 Proving $\sqrt 3$ is irrational. 21 Square Root Inequality 16 What's bad about calling $i$ “the square root of -1”?

Reputation (8,153)

 +5 Proof of a formula involving Euler's totient function: $\varphi (mn) = \varphi (m) \varphi (n) \cdot \frac{d}{\varphi (d)}$ +5 Complex line integral independent of path +5 Identification of a quadrilateral as a trapezoid, rectangle, or square +5 Interpreting the Cayley-Hamilton theorem

Questions (26)

 191 Identification of a quadrilateral as a trapezoid, rectangle, or square 23 Interpreting the Cayley-Hamilton theorem 19 Is there a rule of integration that corresponds to the quotient rule? 18 Proof of a formula involving Euler's totient function: $\varphi (mn) = \varphi (m) \varphi (n) \cdot \frac{d}{\varphi (d)}$ 15 Basis for $\mathbb{Z}^2$

Tags (104)

 77 logic × 9 46 inequality × 7 75 calculus × 33 42 trigonometry × 25 70 algebra-precalculus × 37 39 elementary-number-theory × 13 49 recreational-mathematics × 2 32 proof-verification × 3 47 puzzle × 4 27 rationality-testing