Question

if vector a and b are two vectors such that Ia+bI=a then prove that vector 2a+b is perpendicular to vector b. pls help..​

Answer 1

Explanation:

( A+B)•A= 0

|A|^2+B• A=0

B•A=-|A|^2

|A+B|=|A|

|A|^2+|B|^2+2A•B =|A|^2

|A|^2|B|^2-2|A|^2=|A|^2

|B|^2=|A|^2

|B|=Sqrt 2|A|