What is the mathematical notation for representing a maximum number output?

Question

For example, something like the following:

LowerOfTheTwo(a × b,1000) = c

So, if a = 100 and b = 2, then c = 200.

But, if a = 100 and b = 200, then c = 1000.

Answer 1

I think you may be thinking of $\min\{x_1,x_2,\ldots\}$, which gives the smallest element in the set $\{x_1,x_2,\ldots\}$

For example,

$\min\{1,5\}=1$ and $\min\{-23,45,51,93\}=-23$