The resultant `vec(P) and vec(Q)` is perpendicular to `vec(P)`. What is the angle between `vec(P) and vec(Q)`?

If vec(P).vec(Q)= PQ , then angle between vec(P) and vec(Q) is

If vec(P).vec(Q)= PQ , then angle between vec(P) and vec(Q) is

If vec(P).vec(Q)=1 , then what is the angle between vec(P) and vec(Q) ?

What is the angle between (vec(P)+vec(Q)) and (vec(P)xxvecQ)?

If vec(P).vec(Q) = 0 , then what is the angle between vec(P) and vec(Q) ?

If |vec(P) + vec(Q)| = |vec(P) - vec(Q)| , find the angle between vec(P) and vec(Q) .

If |vec(P) + vec(Q)| = |vec(P) - vec(Q)| , find the angle between vec(P) and vec(Q) .

What can be the angle between (vec(P)+vec(Q)) and (vec(P)-vec(Q)) ?

Given that P=Q=R . If vec(P)+vec(Q)=vec(R) then the angle between vec(P) and vec(R) is theta_(1) . If vec(P)+vec(Q)+vec(R)=vec(0) then the angle between vec(P) and vec(R) is theta_(2) . The relation between theta_(1) and theta_(2) is :-