Update cheatsheet.fr.md

12.temporary_ins/69.waves/30.n3/20.overview/cheatsheet.fr.md

@@ -1555,7 +1555,7 @@ $`\quad\quad \;\; = \cdots`$
   dans l'expression de $`U(\vec{r},t)`$ :   
   <br>
   **$`cos\theta_1+cos\theta_2`$**   
-  $`\quad =\;cos(\theta_{moy}+\Delta\theta_{12})+cos(\theta_{moy}-\Delta\theta_{12})`$   
+  $`\quad\;\; =\;cos(\theta_{moy}+\Delta\theta_{12})+cos(\theta_{moy}-\Delta\theta_{12})`$   
   <br>
   $`\color{blue}{\scriptsize{\left.\begin{align} \quad\quad &cos(a+b)=cos(a)cos(b)-sin(a)sin(b)\\
                      &cos(a-b)=cos(a)cos(b)+-sin(a)sin(b)\end{align}
@@ -1567,7 +1567,7 @@ $`\quad\quad \;\; = \cdots`$
   de même   
   <br>
   **$`cos\theta_1-cos\theta_2`$**   
-  $`\quad = \;cos(\theta_{moy}+\Delta\theta_{12})-cos(\theta_{moy}-\Delta\theta_{12})`$   
+  $`\quad\;\; = \;cos(\theta_{moy}+\Delta\theta_{12})-cos(\theta_{moy}-\Delta\theta_{12})`$   
   <br>
   $`\color{blue}{\scriptsize{\left.\begin{align} \quad\quad &cos(a+b)=cos(a)cos(b)-sin(a)sin(b)\\
                      &cos(a-b)=cos(a)cos(b)+-sin(a)sin(b)\end{align}