Question

if ab=a and ba=b show that a and b are idempotent with example​

Answer 1

Answer:

Let A,B be two matrices such that AB=A and BA=B, how do I show that A⋅A=A and B⋅B=B? Steps I took: • Let A=[abcd] and let B=[wxyz] • [abcd]⋅[wxyz]=[a ...