6 Find x such that the four points A (3, 2, 1) B (4, x, 5), C (4, 2, –2) and D (6, 5, –1) are coplanar.
Q17 Choose the correct answer. Let be two unit vectors and is the angle between them. Then is a unit vector if
Q.14 If are mutually perpendicular vectors of equal magnitudes, show that the vector is equally inclined to .
Q13 The scalar product of the vector with a unit vector along the sum of vectors and is equal to one. Find the value of .
Q10 The two adjacent sides of a parallelogram are . Find the unit vector parallel to its diagonal. Also, find its area.
Q9 Find the position vector of a point R which divides the line joining two points P and Q whose position vectors are externally in the ratio 1: 2. Also, show that P is the mid point of the line segment RQ.
Q8 Show that the points A(1, – 2, – 8), B(5, 0, –2) and C(11, 3, 7) are collinear, and find the ratio in which B divides AC.