Find the dot product of x and y

Question

Let x = [-4, 4,5] and y=[0,0,-3]

Find the dot product of x and y

x.y=?

Answer 1

The dot product of two vectors, A = [A_1, A_{2, ...} A_n] and B = [B₁, B₂, ... B_n] is:

 

∑ A₁B₁  + A₂B₂ + ... A_nB_n

 

For your problem, the dot product would be:

 

= -4*0 + 4*0 + 5*-3

 

= 0 + 0 + -15

 

= -15