Minimum value for a cell

I need to set a minimum value for a cell. I have a formula, 6000+(Product A6-12000x0.4) The problem is the lowest this value can be is 6000. If the value in cell A6 is 12000 or greater it works fine but if it's lower that 12000 I run into trouble for example if A6=10000 the result is 5400. Is there a way to set the cell to the result of the formula or 6000, whichever is greater?