Times dx dt. The derivative of x with respect to t is equal to 12. Times 12. So let's see, nine to the 1 1 2 would be three. Nine to the negative 1 1 2 would be 1 1 3. So this is 1 1 3. So this will all simplify to 1 1 2 times 1 1 3 is 1 1 6.