Contro Systems - Using Partial Fraction Expansion on Transfer Function

[aznkid310]

Homework Statement

A system has damping ratio 0.5, natural freq. 100 rad/s, DC gain of 1. Find the response of the system to a unit step input.

Homework Equations

Im having trouble doing the partial fraction expansion.

The Attempt at a Solution

I have attached a word document using the equation editor.

 

[kentigens]

cover up rules? equating coefficients?