Update cheatsheet.en.md

01.curriculum/01.physics-chemistry-biology/02.Niv2/04.optics/04.use-of-basic-optical-elements/02.mirror/02.new-course-overview/cheatsheet.en.md

@@ -39,7 +39,7 @@ so they are the *most common and cheap*.
 of a *spherical mirror of infinite radius of curvature*.
 Plane mirror, concave and convex spherical mirror
 
-![](plane-concave-convex-mirrors.png)
+![](plane-concave-convex-mirrors.png)<br>
 Fig. 1. a) plane    b) concave    c) convex   mirrors
 
 #### Are plane and spherical mirrors stigmatic?
@@ -57,13 +57,13 @@ Fig. 1. a) plane    b) concave    c) convex   mirrors
 * coming from an object point generally do not converge towards an image 
 * point (see Fig. 2.)
 * 
-![](spherical-mirror-rays-stigmatism-1000-1.jpg)
+![](spherical-mirror-rays-stigmatism-1000-1.jpg)<br>
 Fig. 2. Non stigmatism of a convexe mirror.
 
-![](spherical-mirror-rays-stigmatism-1000-2.jpg)
+![](spherical-mirror-rays-stigmatism-1000-2.jpg)<br>
 Fig. 3. But when we limit the aperture of the mirror,
 
-![](spherical-mirror-rays-stigmatism-1000-3.jpg)
+![](spherical-mirror-rays-stigmatism-1000-3.jpg)<br>
 Fig. 4 . and limit the conditions of use to small angles of incidence and 
 refraction are small, then a point image can be defined : the mirror becomes
 quasi-stigmatic.
@@ -150,16 +150,16 @@ side* of the mirror.<br><br>
 
 * with **real objects** 
 
-![](Thin-spherical-mirror-InfAC-1000.jpg)
+![](Thin-spherical-mirror-InfAC-1000.jpg)<br>
 Fig. 5.  Concave mirror with object between infinity and C
 
-![](Thin-spherical-mirror-CAF-1000.jpg)
+![](Thin-spherical-mirror-CAF-1000.jpg)<br>
 Fig. 6.  Concave mirror with object between C and F/F’
 
-![](Thin-spherical-mirror-FAS-1000.jpg)
+![](Thin-spherical-mirror-FAS-1000.jpg)<br>
 Fig. 7.  Concave mirror with object between F/F’ and S
 
-![](Thin-spherical-mirror-InfAS-1000.jpg)
+![](Thin-spherical-mirror-InfAS-1000.jpg)<br>
 Fig. 8.  Convex mirror