Q1176 (Q1176): Difference between revisions

@@ Property / relevant answers @@
+https://math.stackexchange.com/a/3244185
@@ Property / relevant answers: https://math.stackexchange.com/a/3244185 / rank @@
+Normal rank
+Defining formula:  $\left\vert {\frac {e^{-ixu}-1}{u}}\right\vert ^{2}={\frac {2-2\cos(xu)}{u^{2}}}={\frac {4\sin ^{2}({\frac {xu}{2}})}{u^{2}}}\leq {\frac {4({\frac {xu}{2}})^{2}}{u^{2}}}=x^{2}$ 
\left\vert\frac{e^{-ixu}-1}{u}\right\vert^2=\frac{2-2\cos(xu)}{u^2}=\frac{4\sin^2(\frac{xu}{2})}{u^2}\leq\frac{4(\frac{xu}{2})^2}{u^2}=x^2

Revision as of 23:10, 8 May 2020