For example, f prime could be doing something like this. And even though f prime would be decreasing in this situation, the actual value of the derivative would be positive, which means the function would be increasing in that scenario. So I would rule this one out. For values of x larger than three, as x values increase, the values of f of x decrease. Now that is actually true. This is actually the definition that f is decreasing. As x values increase, the values of f of x decrease.