Well, derivative of x squared, we just bring that exponent out front. It's gonna be two times x to the two minus one, or two x to the first power, or just two x. And then the derivative of three x is just three. So two x plus three. And now we know everything we need to substitute back in here. The derivative of u with respect to x, this right over here is just negative three. V of x, this we know is x squared plus three x.