#70 The Cauchy-Schwarz Inequality 6 years ago (owner) 70 The Cauchy-Schwarz I... #68 MathJax Support $\left( \sum_{k=1}^n a_k b_k \right)^2 \leq \left( \sum_{k=1}^n a_k^2 \right) \left( \sum_{k=1}^n b_k^2 \right)$