00:01
So we want to convert this to the standard form, also known as vertex form.
00:06
And to do that, we want to make a perfect square binomial.
00:10
So we're going to add exactly what it takes to do that.
00:15
And then we're going to also subtract it back out.
00:18
That way we haven't changed the value of the function.
00:21
And how we determine what that is is we take our coefficient of x, or it's also known as b, divide it by two, and then square it.
00:30
So we have one squared, two over two, is one.
00:34
So now we've created a perfect square binomial right here, x, because this is plus, this is plus, and then whatever's in here is being squared, which is one, and that whole thing squared.
00:49
Then we've got minus one, minus one again, makes minus two.
00:53
So that is our standard form.
00:58
And the next thing we needed to do was to sketch a graph of this.
01:04
So first things first, our vertex can be found right here.
01:10
The x value is whatever this is times minus 1.
01:14
So negative 1.
01:16
And our y value is exactly this part.
01:19
So negative 1 comma 2, comma negative 2 is our vertex.
01:24
So it's right there on the graph.
01:27
Then we also can say, well, let's see.
01:31
How about where's the y intercept? well, the y intercept we can easily find by looking at the original function.
01:38
If x is zero, then minus one is our y intercept.
01:44
And there's symmetry.
01:45
So equally as far as to the other side of the vertex, the function also equals minus one.
01:51
And then let's see, what else do we want to try here? how about when x is 1? so if x is 1, then you have 1 plus 1 is 2 squared is 4 minus 2 is 2.
02:05
So when x is 1, y is 2.
02:10
And equally as far to the other side...