0 votes 0 votes A2 − A = 0, where A is a 9×9 matrix. Then (a) A must be a zero matrix (b) A is an identity matrix (c) rank of A is 1 or 0 (d) A is diagonalizable Linear Algebra linear-algebra + – sahil_malik asked Oct 20, 2018 • recategorized Oct 20, 2018 by Mk Utkarsh sahil_malik 289 views answer comment Share Follow See 1 comment See all 1 1 comment reply Shaik Masthan commented Oct 20, 2018 reply Follow Share i am getting, option C. option B and option D you can eliminate easily, For every Zero matrix it is true ( Note that it's rank is 0 )... but there are some other matrices which the given statement is true. ( make only one element in any row is 1 and remaining all elements are 0 ===> rank of this matrix is 1 ) ex 1) make 1st element of 1st row is 1 and take remaining elements are 0 ex 2) make 3rd element of 1st row is 1 and take remaining elements are 0 ..... etc But note that, every matrix which have rank = 1 , doesn't need to satisfy the question. Option C conveying, which matrix satisfies the question, it have rank=1 or 0. 0 votes 0 votes Please log in or register to add a comment.