Question
If $A$ and $B$ are square matrices of size $n\, \times \,n$ such that
${A^2} - {B^2} = \left( {A - B} \right)\left( {A + B} \right),$ then which of the following will be always true?
${A^2} - {B^2} = \left( {A - B} \right)\left( {A + B} \right),$ then which of the following will be always true?