If a , b , c and d are vectors in which | d |=1 and given a + b + c =s d , b + c + d = a , a d =4 , then s is equal to

Step-by-step solution

Given, a , b , c , d are vector and aligned | d | & =1, a + b + c =s d b + c + d & = a , a d =4 aligned Using b + c = a - d in a + b + c =s d , we obtain aligned a + a - d & =s d 2 a =(s+1) d a & = (s+1) 2 d aligned Given, a d =4 (s+1) 2 d d =4 array ll & (s+1) 2 =4 & s=8-1=7 array