00:01
In this problem, we want to prove this statement that a .n can be found using the recursive statement a .n minus 1 plus 4 is also equal to 4n minus 3 for all positive integers greater than 1.
00:16
So we got to do our base case.
00:19
We're going to say for n equals 2 because it's greater than 1.
00:28
A2 would be a1 plus 4, which is equal to 1 plus 4, which is 5.
00:41
And on the right side, we got 4 times 2 minus 3, which is 8 minus 3, which is 5.
00:49
And since the left side and right side are equal, we have shown that a1 is true.
00:58
Now for the inductive step, we assume a k is true, or you can say n equals k is true, both are fine.
01:12
So if a k is true, that means we have a k minus 1 plus 4 is equal to 4k minus 3.
01:25
Then for ak plus 1, we have the following statement...