00:02
We're given negative x to 4 plus 2x square minus 1 equals 0.
00:17
We will find all solutions.
00:23
I'll go ahead and substitute x square with t.
00:35
So it becomes negative t square plus 2t minus 1 equals 0.
00:48
In the first place, i can take the negative parentheses.
00:57
So it's going to be t squared minus 2t plus 1.
01:10
I know how to factor this expression, which is going to be t minus 1 front of square, and in front of it, negative equals 0.
01:30
From here, it implies that t is 1, which means x squared.
01:46
Square is 1 and it gives me two values x of 1 equals positive 1 and x up 2 equals negative 1.
02:06
Now we can substitute in the original one and see whether they work...