Which of the following in an orthogonal matrix

Which of the following is an orthogonal matrix ? ( ⎡ ⎢ ⎣ 6 / 7 2 / 7 − 3 / 7 2 / 7 3 / 7 6 / 7 3 / 7 − 6 / 7 2 / 7 ⎤ ⎥ ⎦ (b) ⎡ ⎢ ⎣ 6 / 7 2 / 7 3 / 7 2 / 7 − 3 / 7 6 / 7 3 / 7 6 / 7 − 2 / 7 ⎤ ⎥ ⎦ (c) ⎡ ⎢ ⎣ − 6 / 7 − 2 / 7 − 3 / 7 2 / 7 3 / 7 6 / 7 − 3 / 7 6 / 7 2 / 7 ⎤ ⎥ ⎦ (d) ⎡ ⎢ ⎣ 6 / 7 − 2 / 7 3 / 7 2 / 7 2 / 7 − 3 / 7 − 6 / 7 2 / 7 3 / 7 ⎤ ⎥ ⎦

For any matrix A, if A^(-1) exists then which of the following is not true ?

In which of the following tissues is the matrix not product of synthesis of its cells?

Which of the following tissues has the minimum intercellular matrix ?

Which of the following is(are) NOT of the square of a 3xx3 matrix with real enteries?

In which of the following type of matrix inverse does not exist always? a. idempotent b. orthogonal c. involuntary d. none of these

Find the characteristic roots of the two-rowed orthogonal matrix [(cos theta,-sin theta),(sin theta,cos theta)] and verify that they are of unit modulus.

During carbohydrate metabolism, NADH is produced in which of the following location(s)? I. Cytosol II. Mitochondrial matrix Ill. Nucleus

Let Aa n dB be two nonsingular square matrices, A^T a n dB^T are the transpose matrices of Aa n dB , respectively, then which of the following options are correct? (correct option may be more than one) (a) . B^T A B is symmetric matrix (b) . if A is symmetric B^T A B is symmetric matrix (c) . if B is symmetric B^T A B is skew-symmetric matrix for every matrix A (d) . B^T A B is skew-symmetric matrix if A is skew-symmetric

Which of the following pair(s) of curves is/are orthogonal?