preCal(Please help)
posted by Hannah .
Use the law of cosines to find the angle Q between the given vectors.
v = 3i + j w = 2i  j

v•w = v wcos Ø
v•w = 6  1 = 5
5 = √10√5cosØ
cosØ = 5/√50
Ø = 45°
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