00:01
Given a couple of pictures of squares inside squares.
00:06
And our first job is to figure out if this process is repeated six more times, what would the total area be? so i've drawn the first two diagrams already, and we're going to try to model a pattern for the areas.
00:21
So the first one, we're being told that it's an original square of 16 by 16.
00:31
So notice that only two of these little triangles are shaded, and we can also think about it in this way.
00:39
If i drew some more hypothetical lines in between, we can see that it forms eight equal triangles, and two of them are shaded.
00:51
So we're really saying one quarter of this area is shaded.
00:58
Now, if one quarter is shaded and we use a highlighter here, this part in the middle, we actually know exactly how much area that is because that's four eights.
01:10
So that's actually half of the original area.
01:14
So in the next picture, you know, we've drawn the square using the midpoints.
01:18
We know that this is already half of the area.
01:22
Of the original.
01:25
And then it turns out, again, by drawing those hypothetical lines, by splitting them up one more time, this actually creates another quarter of the inside square.
01:44
So what we have here is the highlighted part is half of the original area, and then we're taking a quarter of it.
01:55
And it turns out that this pattern is going to hold.
01:58
The next one is going to be one quarter of half of one half a.
02:07
So really one half squared.
02:14
So if we needed to model this to get a general term, a .n, the area of the nth square, is equal to one quarter times one half to the n -minus one...