Update cheatsheet.fr.md

12.temporary_ins/07.geometry-coordinates-prop2/40.n4/20.overview/cheatsheet.fr.md

@@ -113,6 +113,28 @@ $`u_1\,v^1\,+\, u_2\,v^2\,= u\,v\,\dfrac{1}{\cos(a)} \,\left[\cos(a)\cos(\alpha)
 \,+\,\cos(a)\,\sin(\alpha)\,\cos(\alpha)\,\sin(\theta)
 \,+\,\cos(a)\,\sin^2(\alpha)\,\cos(\theta)\right]`$
 
+$`u_1\,v^1\,+\, u_2\,v^2\,= u\,v\,\dfrac{1}{\cos(a)} \,
+\left[\cos(a)\cos^2(\alpha)\cos(\theta)
+\,-\,\cos(a)\cos(\alpha)\sin(\theta)\,\sin(\alpha)
+\,-\,\sin(a)\sin(\alpha)\sin(\theta)\,\cos(\alpha)
+\,-\,\sin(a)\sin^2(\alpha)\,\cos(\theta)
+\,+\,\sin(a)\,\cos^2(\alpha)\,\sin(\theta)
+\,+\,\sin(a)\,\cos(\alpha)\,\sin(\alpha)\,\cos(\theta)
+\,+\,\cos(a)\,\sin(\alpha)\,\cos(\alpha)\,\sin(\theta)
+\,+\,\cos(a)\,\sin^2(\alpha)\,\cos(\theta)\right]`$
+
+à vérifier et terminer
+
+$`u_1\,v^1\,+\, u_2\,v^2\,= u\,v\,\dfrac{1}{\cos(a)} \,
+\left[\cos(a)\cos^2(\alpha)\cos(\theta)
+\,-\,\xcancel{\cos(a)\cos(\alpha)\sin(\theta)\,\sin(\alpha)}
+\,-\,\sin(a)\sin(\alpha)\sin(\theta)\,\cos(\alpha)
+\,-\,\sin(a)\sin^2(\alpha)\,\cos(\theta)
+\,+\,\xcancel{\sin(a)\,\cos^2(\alpha)\,\sin(\theta)}
+\,+\,\sin(a)\,\cos(\alpha)\,\sin(\alpha)\,\cos(\theta)
+\,+\,\xcancel{\cos(a)\,\sin(\alpha)\,\cos(\alpha)\,\sin(\theta)}
+\,+\,\cos(a)\,\sin^2(\alpha)\,\cos(\theta)\right]`$
+