From a7b42708afcf4377990a34e81dd7c2d76c10f5f2 Mon Sep 17 00:00:00 2001 From: Claude Meny Date: Sun, 30 Aug 2020 19:03:42 +0200 Subject: [PATCH] Update textbook.fr.md --- .../04.reference-frames-coordinate-systems/textbook.fr.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/04.reference-frames-coordinate-systems/textbook.fr.md b/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/04.reference-frames-coordinate-systems/textbook.fr.md index 426da4910..81e84a2d6 100644 --- a/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/04.reference-frames-coordinate-systems/textbook.fr.md +++ b/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/04.reference-frames-coordinate-systems/textbook.fr.md @@ -255,9 +255,9 @@ $`=dx\;\overrightarrow{e_x}+dy\;\overrightarrow{e_y}+dz\;\overrightarrow{e_z}`$<
$`||\overrightarrow{dl}||=\sqrt{dl_x^2+dl_y^2+dl_z^2}=\sqrt{dx^2+dy^2+dz^2}`$

$`||\overrightarrow{dl}||=\sqrt{\overrightarrow{dl}\cdot\overrightarrow{dl}}`$ $`=\sqrt{(dl_x\;\overrightarrow{e_x}+dl_y\;\overrightarrow{e_y}+dl_z\;\overrightarrow{e_z})\cdot -(dl_x\;\overrightarrow{e_x}+dl_y\;\overrightarrow{e_y}+dl_z\;\overrightarrow{e_z})`$ +(dl_x\;\overrightarrow{e_x}+dl_y\;\overrightarrow{e_y}+dl_z\;\overrightarrow{e_z})}`$ $`=\sqrt{(dl_x)^2\;(\overrightarrow{e_x}\cdot\overrightarrow{e_x})+(dl_y)^2\;(\overrightarrow{e_y}\cdot\overrightarrow{e_y}) -+(dl_z)^2\;(\overrightarrow{e_z}\cdot\overrightarrow{e_z})`$ ++(dl_z)^2\;(\overrightarrow{e_z}\cdot\overrightarrow{e_z})}`$ $`+(2\,dl_x\,dl_y)\,(\overrightarrow{e_x}\cdot\overrightarrow{e_y})`$ $`+(2\,dl_x\,dl_z)\,(\overrightarrow{e_x}\cdot\overrightarrow{e_z})`$ $`+(2\,dl_y\,dl_z)\,(\overrightarrow{e_y}\cdot\overrightarrow{e_z})`$