And what I'm concerned with is finding the area under the curve y is equal to f of x, so that's my y axis. This is my x axis. And let me draw my function. My function looks like this, at least in the first quadrant. That's where I'll graph it for now. I could also graph it, obviously, in the second quadrant. But what I care about is the area under this curve and above the positive x axis between x equals 1 and x equals 4.