And if I have 7 factorial divided by 6 factorial, that's just 7. Or if I have 3 factorial divided by 2 factorial, that's just 3. You can work it out. 10 factorial divided by 9 factorial, that's 10. So n factorial divided by n minus 1 factorial, that's just equal to n. So this is equal to n times x to the n minus 1. So that's the derivative of x to the n. n times x to the n minus 1. So we just proved the derivative for any positive integer, x to the power n, where n is any positive integer.