Answer:
81
Step-by-step explanation:
Evaluating v • w
Recall: Given vectors a and B in Cartesian plane, x, y and z
vector a = [ax ay az] and b = [bx by bz]
The dot product is :
a•b = axbx + ayby + azbz
Using the relation above,
v • w = (5*9) + (-4*-2) + (4*7)
v • w = 45 + 8 + 28
v • w = 81
Hence, v • w = 81
