(Solved):   Given stiffness matrix \( [K] \) and mass matrix \( [M] \) as below; \[ \begin{array}{l} { ...

 

Given stiffness matrix \( [K] \) and mass matrix \( [M] \) as below; \[ \begin{array}{l} {[\boldsymbol{K}]=\left[\begin{array}{llll} 4 & 3 & 2 & 0 \\ 3 & 3 & 1 & 0 \\ 2 & 1 & 2 & 1 \\ 0 & 0 & 1 & 4 \end{array}\right]} \\ {[\boldsymbol{M}]=\left[\begin{array}{llll} 3 & 1 & 2 & 0 \\ 1 & 2 & 1 & 0 \\ 2 & 1 & 3 & 1 \\ 0 & 0 & 1 & 2 \end{array}\right]} \end{array} \] And \( \alpha=-0.382 \) and \( \beta=-0.382 \) and the transformation matrix [P] is given as below; \[ [\boldsymbol{P}]=\left[\begin{array}{llll} 1 & 0 & \alpha & 0 \\ 0 & 1 & 0 & 0 \\ \beta & 0 & 1 & 0 \\ 0 & 0 & 0 & 1 \end{array}\right] \]