00:01
Since there's three problems, i'm just going to jump right into the work.
00:04
The thought process is that we can only do the fourth root of numbers that are greater than or equal to zero.
00:11
So at this point, i would factor out an x, you're left with x minus three, and i would look at the critical numbers of zero and three, and then make a number line and just discuss what happens.
00:24
So it is okay for you to equal zero.
00:27
So i'm going to close these bounds.
00:29
But then i'm going to test different numbers.
00:31
Like what happens if i plug in negative one? well, when you square negative one, you get one plus three is four, which is a positive number.
00:41
So we're good to do numbers on that side.
00:44
But now i'm going to try a number like x equals positive one, in which case you get one minus three now, which is negative two.
00:51
And that's not okay.
00:53
I'll put an x there.
00:54
That's bad.
00:54
And then do a number like x equals four.
00:58
And this time i get 16 minus 12, three times four...