PROPOSITIO IX.
Ductis a puncto superno perpendiculari, &
inclinata ad planum Orizontale, & a pun
cto inferno perpendicularis ducta normali
ad inclinatam, impetus inclinatae in pun
ctis, in quibus secat normalem, & orizon
talem, sunt ut perpendicularis, & inclinata.
inclinata ad planum Orizontale, & a pun
cto inferno perpendicularis ducta normali
ad inclinatam, impetus inclinatae in pun
ctis, in quibus secat normalem, & orizon
talem, sunt ut perpendicularis, & inclinata.
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