00:01
So we want to find our coefficient in front of x to power of 7.
00:05
So if you want to find our x to the power of j term, that's going to be n times n minus j, a to the power of n minus j, and x to the power of j.
00:17
So looking at this, we see that our j value is 7.
00:21
Our n value is given to be 12.
00:24
And then our other term, a, that's equal to negative 1.
00:29
And let's also note that instead of x, we have 2x.
00:32
So actually we would have 2x to the power of 7 like that.
00:38
And then let's plug in our equation.
00:41
So that's n, which is 12, n minus j, that's 7...