How write actionscript of laplace transform in flash

Hello…

I have problem about math.

I want write function of laplace transform in flash.
… …

X(s)=kds^2 +kps+Ki;
F(s)=s^3 +(10+kd)*s^2 +(20+Kp)*s+Ki;
Gc(s)=X(s)=/F(s);
… …

how i write code(actionscript) in flash
when Kp Ki Pd is value of user input.
and S is Laplace transform
Help me, Please
Thanks yous.:blush: