48 Why does $1+2+3+\cdots = -\frac{1}{12}$? 24 Prove $\sin^2\theta + \cos^2\theta = 1$ 16 Why exactly does the distributive property work? 15 Prove $\sin^2\theta + \cos^2\theta = 1$ 11 What does the Circle really mean?

### Reputation (6,330)

 +10 Do equal bases imply equal powers? +10 Approximating Logs and Antilogs by hand +10 Why does $1+2+3+\cdots = -\frac{1}{12}$? +10 Prove $\sin^2\theta + \cos^2\theta = 1$

### Questions (51)

 93 Can the golden ratio accurately be expressed in terms of $e$ and $\pi$ 52 Sheldon Cooper Primes 36 Prove $\sin^2\theta + \cos^2\theta = 1$ 23 Given two blank rulers, measure any length 18 Approximating Logs and Antilogs by hand

### Tags (103)

 49 trigonometry × 24 36 algebra-precalculus × 20 48 divergent-series × 3 28 calculus × 22 48 analysis × 2 19 arithmetic × 6 48 complex-analysis 15 integration × 9 48 riemann-zeta 15 circles × 4

### Bookmarks (132)

 722 What's an intuitive way to think about the determinant? 667 Splitting a sandwich and not feeling deceived 426 Why does $1+2+3+\cdots = -\frac{1}{12}$? 172 Why $\sqrt{-1 \cdot {-1}} \neq \sqrt{-1}^2$? 133 List of interesting math podcasts? [closed]