exponentially means A^X, if so pls explain what is basis A and what is exponent X.
A is your hashrate.
X depends on how much you choose to reinvest. Probably something like 1.001. And yes, it grows exponentially albeit slowly.
Okay, I have A=1000.00 GH/s, what if I reinvest 100%, what's the calculation, how can I calculate exponent?
Enter 1000 GH/s (or 1 TH/s) and find how much you'll make before fees, subtract fees, divide by 0.49 (current price per GH/s). You should be able to figure out the rest.