Question

Prove that product of 2 orthogonal matrices is orthogonal

Answer 1

Answer:

Step-by-step explanation:

If

QTQ=I

RTR=I,

then

(QR)T(QR)=RT(QTQ)R=RTR=I.

Of course, this can be extended to n many matrices inductively.

Answer 2

Answer:

orthogonal matrix is a real square matrix whose columns and rows are orthogonal unit vectors (orthonormal vectors). is the identity matrix.