**Solution:**

## The dots above q

_{1}and q_{2}represent the time derivative of q_{1}and q_{2}, respectively. The addition of negative lambdas (or Eigenvalues) to the main determinants enable us to solve for these values and consequently for q_{1}and q_{2}. The values of q_{1}and q_{2}can be obtain from the following equations:

C

_{1}and C_{2}are determined from initial conditions. For example, the mass in C_{1}and C_{2}at initial time.

A.9.c-2