00:01
Okay, so for this problem, we are told to find the original function f of x given the slopes of x, f prime of x, and the coordinate.
00:10
An x, y coordinate.
00:11
And so when we're doing this, we need to use integration.
00:16
And so we want an unbounded integration so we get a function back.
00:21
So, let me change colors.
00:25
This is our integrand.
00:27
Then we're going to put our function f prime of x into it.
00:31
Of this d x.
00:33
And so when we're just dealing with this, we're going to raise the power by one.
00:41
And so this is one plus one and divide that by that, which would be two.
00:48
When we have a constant, we're just going to add an x onto it.
00:52
And so that would give us 4x squared because we raise the power and we're dividing by 2 plus c.
01:06
And this plus c is very important.
01:08
So now let's just simplify this down.
01:12
So we have 2x squared plus x plus c is equal to our function f of x.
01:19
And we know we know we have a 1 -2 right here as a coordinate.
01:25
We have x's here.
01:27
This f of x would be our 2 or our y.
01:29
And so now we're just going to plug everything in and solve for c.
01:34
So then we have, oops.
01:38
We have 2 times 1 squared plus 1 plus c.
01:43
It's equal to 2.
01:44
So we have 2 times 1 squared is 2 plus 1 is 3.
01:49
So i'm just going to subtract 3 on both sides to get my c by itself.
01:54
And so then we would get that c equals negative 1...