Question

if two vectors 2i+j+k and i+aj+3k are perpendicular to each other then find the magnitude of a​

Answer 1

Answer:

a = -5

Explanation:

Using formula :- X.Y = xy costheta

X = 2i + j + k

Y = I + aj + 3k

X.Y = 2 + a + 3 = 5+a

cos theta = cos 90° = 0

X.Y = 0

a = -5

Answer 2

Answer:

if two vectors are perpendicular then