00:02
To solve the equation x minus 2 cubed is equal to x cubed minus 2, we need to expand the left side of the equation first.
00:11
Let's rewrite x minus 2 cubed as x minus 2 times the square of x minus 2.
00:22
And then we can apply the square of a binomial, special product rule, and that will give us x squared minus 4x plus 4.
00:33
Using the distributive property, we're then going to multiply the other x minus 2 factor.
00:42
X times x squared is x cubed, x times negative 4x minus 4x squared, x times 4x squared, x times 4x, plus 4, and then negative 2 times x squared, negative 2x squared, negative 2 times negative 4x, plus 8x, and finally, minus 8.
01:02
This is going to be simplified using our like terms to x cubed minus 6x squared plus 12x minus 8.
01:19
Now bringing down the other half of the equation, the right side of the equal sign, set it equal to x cubed minus 2.
01:29
The first rule for solving any polynomial equation is to set it equal to zero.
01:34
So let's use inverse operations, subtract x cubed, add two to both sides, and that will leave us with negative 6x squared plus 12x minus 6 is equal to 0.
01:55
Let's start the factoring process.
01:58
There is a greatest common factor of negative 6.
02:02
When we divide that out, we're left with x squared plus minus 2x.
02:09
Plus 1 is equal to 0...