So the derivative of this, f prime of x, this is pretty straightforward, the derivative of 3x to the fourth, 4 times 3 is 12. 12x to the, we'll just decrement the 4 by 1, 3. You just multiply times the exponent and then decrease the new exponent by 1. Minus 3 times 4 is 12, times x to the, 1 less than 3 is 2. And then the derivative of a constant, the slope of a constant you can almost imagine, is 0. It's not changing, a constant by definition isn't changing. So that's f prime of x.