00:01
The first thing i should notice is that this is a polynomial with four terms.
00:04
Right.
00:04
Whenever i have four terms, i could think about factoring by grouping.
00:09
What does factor by grouping mean? well, what i could do is i could group the first two terms and group the next two terms.
00:16
And since with my first term, the third term, i have a negative.
00:20
I'm going to group that negative.
00:21
There, this is technically adding.
00:24
And then i'm going to find the greatest common factor of each group.
00:26
What can i divide both of these by? well, x the third is just x times x times x, right? x squared is x times x.
00:35
How many x do they have in common? well, they have one, two x is in common, so i could pull out an x squared from each term.
00:41
So if i divide each term by x squared, i'm left with one x, minus x squared over x squared is just one.
00:49
What about my next one? what's my greatest common factor here? well, we're both divisible by three, but the trick with factoring by grouping is i want to get the same expression x minus 1.
00:59
So if i factor out of 3, i have a negative x plus 1.
01:02
So i'm going to take out a negative 3...