00:01
Okay, so we have the curve x squared minus 4x, and we want to know the slope of the line tangent to the curve at the point 1, negative 3.
00:15
Okay, so we're just going to do something similar.
00:18
We're going to take a small number near zero, so either positive negative, and then look at this slope of, okay, x plus h, squared minus 4 times x plus h so that's just a little bit away sorry not x 1 plus h yeah so i'm looking at the second line between either uh 1 minus h to 1 or 1 to 1 plus h so 1 there we go and then minus x squared minus 4 we're going to evaluate it 1 okay so 1 squared minus 4 times 1.
01:24
So i'm evaluating, i'm looking at the curve at 1 plus h and then subtracting the point on the curve at 1, and then dividing by the distance between 1 plus h and 1.
01:36
Well, that's h.
01:37
Okay, and then i just want to see what happens.
01:41
Well, on top, we have 1 plus 2h plus h squared, minus 4, minus 4, h.
01:57
Minus 1 minus 4.
02:06
Okay, all over h.
02:10
Okay, and then 1 minus 1, that's 0.
02:12
And then we have minus 4, minus 4 is 0.
02:16
So this is gone...