Question

QI Prove that vectore à and B are parallel ro each other
À = 4i+ 3j +k
, B = 12 i+ 9j + 3K​

Answer 1

Explanation:

1. first method :-

A=4i +3j+k

B = 12i+9j+3k

= 3(4i+3j+k)

=3A

since B is equal to scalar mutiple of A.

hence A and B are parallel

2. second method:-

finding angle using formula

cos x = A.B

।A। ।B।

hence cosx= (4i+3j+k).(12i+9j+3k)

(26)½(234)1/2

cosx = 48+27+3

(6084)½

cosx = 78

78

cosx=1 => x=0

Angle between two vectors is zero

therefore,A and B vectors are parallel