Question

Solve the following system of equations, using matrices : 2/x + 3/y + 10/z = 4, 4/x – 6/y + 5/z = 1, 6/x + 9/y – 20/z = 2 where x, y, z ≠ 0

If A = [1 cot x; –cot x 1], show that A′A⁻¹ = [–cos 2x –sin 2x; sin 2x –cos 2x].

Let A = [a b; c d] be a square matrix such that adj A = A. Then, (a + b + c + d) is equal to :

If A = [2 0 0; 0 3 0; 0 0 5], then A⁻¹ is :