If the position vectors of P and Q be respectively `hati+3hatj-7hatk and 5hati-2hatj+4hatk and vec(PQ)`

If the positin vector of P and Q be respectively hati+3hatj-7hatk and 5hati-2hastj+4hatk find vec(PQ)

If the position vectors of A and B respectively hati+3hatj-7hatk and 5 hati-2hatj+4hatk , then find AB

If the position vectors of P and Q are (hati+3hatj-7hatk) and (5hati-2hatj+4hatk) , then |PQ| is

If the position vectors of P and Q are hati+2hatj-7hatk and 5hati-2hatj+4hatk respectively, the cosine of the angle between PQ and Z-axis is

If the position vectors of A and B are hati+3hatj-7hatk and 5hati-2hatj+4hatk , then the direction cosine of AB along Y-axis is

If the position vectors of P and Q are hati+2hatj-7hatk and 5hati-3hatj+4hatk respectively, the cosine of the angle between vec(PQ) and z-axis is

If position vectors of P,Q,R,S be respectively 2hati+4hatk, 5hati+4hatj+4hatk, -4hati-8hatj+hatk, 2hati+hatk , prove that RS is parallel to PQ and is twice of PQ.

The position vectors of the point P,Q,R and S are respectively hati+hatj+hatk, 2hati+5hatj, 3hati+2hatj-3hatk and hati-6hatj-hatk . Prove that the lines PQ and RS are parallel and the ratio of their length is 1/2