Update 12.temporary_ins/90.electromagnetism-in-vacuum/20.electromagnetic-waves-vacuum/20.overview/cheatsheet.fr.md

Update 12.temporary_ins/10.electrostatics-vacuum/40.gauss-theorem-applications/15.gauss-local-method/10.main/textbook.fr.md

Update 12.temporary_ins/10.electrostatics-vacuum/40.gauss-theorem-applications/10.gauss-integral-method/10.main/textbook.fr.md

Update 12.temporary_ins/10.electrostatics-vacuum/40.gauss-theorem-applications/05.gauss-symetries-invariances/10.main/textbook.fr.md

Update 12.temporary_ins/08.conservative-vector-fields/20.conservative-vector-fields-properties/20.overview/cheatsheet.fr.md

Update 12.temporary_ins/10.electrostatics-vacuum/30.gauss-theorem-demonstration/20.overview/cheatsheet.fr.md

Update 12.temporary_ins/04-math-tools/10.differential-and-integral-calculus/20.differential-calculus/20.overview/cheatsheet.fr.md

Update 12.temporary_ins/04-math-tools/10.differential-and-integral-calculus/30.integral-calculus/20.overview/cheatsheet.fr.md