For all real values of θ, the matrix cos(θ)-sin(θ)sin(θ)cos(θ) is always:

If A is a 2×2 matrix and B is a 2×2 matrix, which statement is correct regarding the product AB?

If A = [2 05 6] and B = [3 64 1], what is A + B?

If A is a 2×2 matrix and B is a 2×2 matrix, which statement is correct regarding product matrix AB?

If for a matrix A, |A| = 6 and adj A = [1, -2, 4; 4, 1, 1; -1, k, 0], then the value of k is equal to:

Let A, B and C be three 2 × 2 matrices with real entries such that B = (I + A)−1 and A + C = I. If BC = [1−5][−12] and CB [x1][x2] = [12][−6], then the value of x1 + x2 is: