So we want to find where this thing over here is equal to 0. And once again, for this to be equal to 0, the numerator has to be equal to 0. This denominator can never be equal to 0 if we're dealing with real numbers, which I think is a fair assumption. So let's see where our numerator can be equal to 0 for the second derivative. So let's set the numerator of the second derivative. 27 times 12 x squared minus 4x to the 6th is equal to 0. Remember, that's just the numerator of our second derivative.