Question

A square matrix A of order n is called involutive if A^2=In
Show that the dterminant of involutive imatrix is 1 or-1

Answer 1

Answer:

1 or -1

Step-by-step explanation:

as A^2 =In

taking determinant on both sides

|A|^2 =|In|

as |In|=1

|A|^2=1

hence, |A|=1 or -1