Question

cos a
- sin a
7. IfA-
2).
then for what value(s) of a is an identity matrix ?
sin a
ços​

Answer 1

this is your answer dear

$Given, A=[cosαsinα−sinαcosα] is identity matrix.</p><p></p><p></p><p>Then,</p><p></p><p></p><p>A=[cosαsinα−sinαcosα] =[1001] </p><p></p><p></p><p>or, cosα=1 and sinα=0</p><p></p><p></p><p>or, α=0.</p><p></p><p>$