00:01
So i don't know which one of these problems you wanted solved here.
00:04
If you want all of them solved, you'll have to submit the other parts as separate questions.
00:11
I believe you wouldn't have to pay anything extra for doing that or anything along those lines.
00:15
You can ask unlimited problems or you can ask an unlimited number of questions.
00:20
That being said, for this first one, we're asked on what intervals is f of x equals x the power 4 minus 4x cubed, both decreasing and concave up? show your thinking using sign charts for f prime and f double prime, and you are also asked to attach a desmos graph.
00:36
I won't be doing that, but i will show the process of the differentiation.
00:41
So if we have f of x equals x to the power of...
00:45
Let me double check, yeah, x power of 4, minus 4x to the power of 3, then f prime of x, the first derivative, will be 4x cubed, minus 12x squared.
00:57
We can factor out the 4x squared from that, writing this as 4x squared times just x minus 3...