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dBrandon/dC
#3
Feb5-11, 01:24 PM
P: 21
Wolfram didn't mention a constant, though I know I could use one. I just didn't think I needed to. ... I'm including two pictures here - screenshots of an online graphing calculator (http://www.coolmath.com/graphit/) where I plugged in these equations. In both of them, I've zoomed into the region of x = 0 to about 3.14.Capture1.bmp Capture2.bmp The first picture is a graph of the original equation. As you can see, the curve is entirely in the y+ quadrant. But in the second picture, after the equation is integrated, the first part of the curve is negative. It's been a long time since I took a calculus class, but isn't an integration supposed to give me the area under the curve? And when I solve the integrated equation for, let's say, x = 0.5, shouldn't that give me the area under the curve down to the y = 0 line, and from x = 0 to x = 0.5? But when I solve for x = 0.5, I get -0.027. That makes sense given the second picture, but it doesn't make sense to me given the first picture. Where's the negative area under the curve in the first graph?