So it's going to be 5x to the fourth power, which is going to be equal to 2 times 5 is 10x to the fourth. So 2x to the fifth, you can literally just say, OK, the power rule tells me the derivative of that is 5x to the fourth. 5 times 2 is 10. So that simplifies our life a good bit. We can now, using the power rule and this one property, take the derivative of anything that takes the form ax to the n power. Now let's think about another very useful derivative property. And these don't just apply to the power rule.