trigonometry pages: create a "Special matricial processing" subsection for *m pages
Reported by Samuel GOUGEON (@sgougeon)
BUG DESCRIPTION:
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*m trigonometric functions are special, very different from other ones in the trigonometry section.
They are quite puzzling for students. Other usual functions work also with matrices, but element-wise.
*m pages should be gathered in a dedicated subsection.
OTHER INFORMATION:
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https://help.scilab.org/docs/6.0.1/en_US/section_38e1eff4be326517b8a24643760b8667.html