Find the indicated dot product.

Question

r = <9, -7, -8>, v = <3, 4, 7>, w = <6, -9, 7> 

v ⋅ w

Answer 1

r = <9, -7, -8>, v = <3, 4, 7>, w = <6, -9, 7> 

Dot product is a scaler product

if a =<x1,y1,z1>   b= <x2,y2,z2>

a ⋅ b =x1x2+y1y2+z1z2

v ⋅ w =(3)(6)+(4)(-9)+(7)(7)

       =18-36+49

       = 31