a) To verify (u v) w = u (v w), we can use the distributive property of the dot product:
(u v) w = (u ∙ v) w = (v ∙ u) w = v (u ∙ w) = v (w ∙ u) = u (v ∙ w)
Therefore, (u v) w = u (v w).
b) To verify c(u v) = cu cv, we can use the distributive property of scalar multiplication:
c(u v) = c(u ∙ v) = (cu) v = (cv) u = cu cv
Therefore, c(u v) = cu cv.