Question

If A and B are two matrices such that AB = A and BA = B, then B² is equal to :

A. B 

B. A 

C. 1 

D. 0

Answer 1

Option (A).

AB = A ----- (i) 

BA = B ------(ii) 

From equation (ii),

B × (AB) = B 

B²A= B 

From equation (ii),

B²A = BA 

B² = B 

Option (A) is the answer.