00:01
Okay, so this problem gives you a function of x squared times x4 minus x, and they want you to state, determine whether this expression, this relationship is true or false.
00:15
And this relationship says that the double derivative of a function is equal to the derivative of x squared times the derivative of x4 minus x, which then equals to 2x times 4x cubed minus 1.
00:28
And this, the statement is false, false.
00:35
This is because the derivative of a function is not a product.
00:41
It's because the derivative of a product, if we have a product, so for this function we have x squared times x4 minus x.
00:48
The derivative of this is not the product of their derivatives.
00:52
You can't take them individually, like how you do it with sums, and take the derivative of them individually and then multiply them.
01:00
You're not allowed to do that.
01:03
We have to use something called the product rule, which we'll learn a later section.
01:09
But for the time being, the way we're supposed to approach the problem is to factor in the x squared so you end up with x6 minus x cubed for your function...