`A=[(cos alpha,-sin alpha),(sin alpha,cos alpha)]` and `A+A^(T)=I`, find the value of `alpha`.

If A = [ (cos alpha ,- sin alpha ),(sin alpha ,cos alpha)] , then A + A' = I then the value of alpha is :

If A=[[cos alpha,-sin alphasin alpha,cos alpha]] then AA'=I, if the value of alpha is

A=[[Cos alpha,sin alpha],[-Sin alpha,cos alpha]] then A^(2)

A=[[cos alpha,sin alpha],[-sin alpha,cos alpha]] , then find | A |

If A=[[cosalpha, sin alpha] , [-sin alpha, cos alpha]] and A^(-1)=A' then alpha=

If A=[[cosalpha, -sin alpha] , [sin alpha, cos alpha]] then A+A'=I then alpha=