Answer:
6
Not perpendicular
Explanation:
Generally, when we have two vectors, (x1, x2, x3...xn) and (y1, y2, y3...yn) the inner product is given by x1*y1+(x2*y2)+(x3*y3).....(xnyn)
If the above sum is zero then the two vectors are perpendicular else they are not.
Given (3, 1, 4) and (2, 8, -2)
The inner product will be
(3*2)+(1*8)+(4*-2)=6+8-8=6
The inner product is 6 hence not perpendicular.