Consider the following LQR problem. T min J = [x] (t) Lac(t) + u] (t) u(t) ] dt subject to i = Ax + Bu, x(0) = to where B is an orthonormal matrix (i.e., it is square and BB" = BB = I). Apply calculus of variations to find the minimizing control law among all feedback control laws of the form u(t) = -K (t) x(t)