The unit vector (a +b j ) is perpendicular to ( + ) . The value of ^ b^ is

Step-by-step solution

array l n =a i +b j r = i + j array If n is perpendicular to the vector r = i + j n r =0a+b=0b=-a . . .(1) The magnitude of unity vector is 1 . a²+b² =1 a²+a² = 2 a=1( from equation 1) a= 1 2 a= 1 2 and from equation (1), we get b=- 1 2 The correct option is D.