Top network posts

• 18 How did Euler realize $x^4-4x^3+2x^2+4x+4=(x^2-(2+\alpha)x+1+\sqrt{7}+\alpha)(x^2-(2-\alpha)x+1+\sqrt{7}-\alpha)$?
• 12 Is it normal that a pure math student doesn't know vector analysis?
• 12 Positive and negative complex numbers?
• 10 How to prove the inequality $\det (AA^T) \ge 0$?
• 9 How do people on MSE find closed-form expressions for integrals, infinite products, etc?
• 9 If $R$ is a local ring, is $R[[x]]$ (the ring of formal power series) also a local ring?
• 7 Every $x \in (0,1]$ can be represented as $x = \sum_{k=1}^{\infty} 1/{n_k}$, such that $n_{k+1}/n_k\in \{2,3,4\}$
• View more network posts →