www.mathsenligne.com STI2D - 1G1 - PRODUITSCALAIREDANSLEPLAN EXERCICES 3B EXERCICE 3B.1
Déterminer le cosinus de (\s\up8(®,\s\up8(®) puis l’angle (\s\up8(®,\s\up8(®) (ou une approximation, si c’est possible) :
= 4 = 8 \s\up8(®.\s\up8(® = 32
cos (\s\up8(®,\s\up8(®) =
(\s\up8(®,\s\up8(®) =
= = 2 \s\up8(®.\s\up8(® = 2
cos (\s\up8(®,\s\up8(®) =
(\s\up8(®,\s\up8(®) =
= 2 = 3 \s\up8(®.\s\up8(® = -6
cos (\s\up8(®,\s\up8(®) =
(\s\up8(®,\s\up8(®) =
= 1 = 6 \s\up8(®.\s\up8(® = -3
cos (\s\up8(®,\s\up8(®) =
(\s\up8(®,\s\up8(®) =
= 3 = 7 \s\up8(®.\s\up8(® = 14
cos (\s\up8(®,\s\up8(®) =
(\s\up8(®,\s\up8(®)
= 6 = 1 \s\up8(®.\s\up8(® = 7
cos (\s\up8(®,\s\up8(®) =
(\s\up8(®,\s\up8(®) =
= 2 = \s\up8(®.\s\up8(® = -3
cos (\s\up8(®,\s\up8(®) =
(\s\up8(®,\s\up8(®) =
= 3 = 2 \s\up8(®.\s\up8(® = -6
cos (\s\up8(®,\s\up8(®) =
(\s\up8(®,\s\up8(®) =
EXERCICE 3B.2
Dans chaque cas, indiquer si le produit scalaire \s\up8(®.\s\up8(® est positif (>0), négatif (<0) ou nul (=0).
. ……… . ……… . ………
. ……… . ………
\s\
up
\s\
up
\s\up8(®.\
s\up8(® …
\s\
up
\s\
up
\s\up8(®.\
s\up8(® …
\s\
\s\ up up
\s\up8(®.\
s\up8(® …
