Arithmetic functions using fixed point [Verilog]

Hello,

I need to implement 1-exp(-a/b)

I was thinking

1. convert integer (a and b) to fixed point

2. Then perform functions such as division and exponential equation

Do you know any library or function for this? I heard about mega functions but that is for floating point and it will require alot of resources that will be needed for other computations in my system (such as convolution)

Thank you,