Question

Evaluate the expression. r = <5, 9, -4>, v = <3, 3, -8>, w = <9, -6, -1> v ⋅ w

Answer 1

17

Explanation:

do (a1 x a2) + (b1 x b2) + (c1 x c2)

(a1 x a2) = 3(9) = 27

(b1 x b2) = 3(-6) = -18

(c1 x c2) = 8

27 + (-18) + 8 = 17

When finding dot product, always add up the results, otherwise it's incomplete!

Answer 2

< 27, -18, 8>

Explanation:

Let v = <3, 3, -8>, w = <9, -6, -1>

v*w = < 3*9, 3*-6, -8*-1>

< 27, -18, 8>