Let A=
[0 2b c]
[a b -c]
[a -b c]
be an orthogonal matrix , then the values of a,b,c are
a. b=±1/√6,c=±1/√3
b. a=±1/√2,b=±1/√6
c. a=±1/√2,c=±1/√6
d. all of these