contestada

if vectors A&B are non zero vectors ,is it possible for their dot product and cross product to be zero? explain.​

Respuesta :

TimMil

Answer:

It can be proved that it’s impossible.

The dot product is defined as:

a⋅b=∥a∥∥b∥cos(θ)  

where  θ  is the angle between  a  and  b .

The cross product is defined as:

a×b=∥a∥∥b∥sin(θ)n^  

and the magnitude of this is given by:

∥a×b∥=∥a∥∥b∥sin(θ)  

We also know that:

cos2(θ)+sin2(θ)=1  

We can substitute the dot product and the magnitude of the cross product in here, to find:

(a⋅b)2+∥a×b∥2=∥a∥2∥b∥2  

We’ve specified that  a  and  b  are non-zero vectors, so the right hand side cannot be zero. As a result, at least one of  (a⋅b)2  or  ∥a×b∥2  must be non-zero.

Step-by-step explanation: