So if you think about the slope of the line that connects these two points, so this line that connects those two points all the mean value theorem, I'm going to do that in a different color, all the mean value theorem tells us is that there's a point between one and three where the slope of the tangent line has the exact same slope, so if I were to eyeball it, it looks like it's right around there although we are actually going to solve for it, so some point where the slope of the tangent line is equal to the slope of the line that connects these two end points and their corresponding function values, so that is c, that would be c right over there. So really we just have to solve this, so let's first just find out what f prime of x is and then we could substitute a c in there and then we can evaluate this on the right hand side. So I'm going to rewrite f of x f of x is equal to and I'm going to write it as four x to the minus three to the one half power, it makes it a little bit more obvious that we can apply the power rule and the chain rule here, so f prime of x is going to be the derivative of four x minus three to the one half with respect to four x minus three, so that is going to be one half times four x minus three to the negative one half and then we're going to multiply that times the derivative of four x minus three with respect to x, well, derivative of four x with respect to x is just four and the derivative of negative three with respect word x well that's just going to be zero, so the derivative of four x minus three is four, so times four. So f prime of x, f prime of x is equal to four times 1 1⁄2, which is two over the square root of four x minus three. Four x minus three to the 1 1⁄2 would just be the square root of four x minus three, but it's the negative 1 1⁄2, so we're gonna put it in the denominator right over here. And so f prime of c, we could rewrite this as two over the square root of four c minus three. And what is that going to be equal to?