Determinantshard
0:00.0

A matrix QQ is orthogonal if QTQ=IQ^T Q = I. Taking determinants of both sides: det(QTQ)=det(I)=1\det(Q^T Q) = \det(I) = 1. Using det(QT)=det(Q)\det(Q^T) = \det(Q), we get [det(Q)]2=1[\det(Q)]^2 = 1. What are the possible values of det(Q)\det(Q) for any orthogonal matrix?