Q1 of 181 Page 1073

If and are two equal vectors the x + y + z = ?

Since, these two vectors are equal, therefore comparing these two vectors we get,

x = 3 , - y = 2 , - z = 1

⇒x = 3,y = - 2,z = - 1

∴x + y + z = 3 + ( - 2) + ( - 1) = 3 - 2 - 1 = 0

Ans:x + y + z = 0

Using vector method, show that the points A(4, 5, 1), B(0, -1, -1), C(3, 9, 4) and
D(-4, 4, 4) are coplanar.

Find the value of λ for which the points A(3, 2, 1), B(4, λ, 5), C(4, 2, -2) and D(6, 5, -1) are coplanar.

Ans. λ = 5

Write a unit vector in the direction of the sum of the vectors and

Write the value of λ so that the vectors and are perpendicular to each other.