#What does the question mean?
sage plankBOT
tacit fogBOT
Craig
gilded nova
the chain rule states that dy/dx= dy/du * du/dx
after you have that you can replace any left over (u) in your equation with the given expression for u in terms of x
dapper crag
the chain rule states that dy/dx= dy/du * du/dx
Can you link me to info on this? I know the chain rule very well. Still don't understand the question. I found the derivative of a). It is 3u^2 + 6u + 3. Now what is the next step?
I have done way harder chain rule questions. I don't understand what they are asking.
gilded nova
you can think of it as if you were just given y=(1/x^2 +1)^3 and told to differentiate via the chain rule, it works the same way.
What youve done so far is calculate dy/du
so you need to find du/dx and multiply that by what youve done so far
dapper crag
So how do i do that?
gilded nova
what is du/dx?
dapper crag
I don't know. i don't understand what you are asking. Give me a function and I can solve it easily.
i found dy/du
gilded nova
u=1/x^2 is given in the question
gilded nova
dw about it
gilded nova
that still just dy/du
gilded nova
So do i just sub it in and then a = 3/x^2 + 6/x^2 + 3
you need dy/dx so you need to multiply this by du/dx
gilded nova
So do i just sub it in and then a = 3/x^2 + 6/x^2 + 3
also the first term would be 3/x^4 here
gilded nova
looks good
dapper crag
Yeah because u’ = -2/x^3 so I just did (3/x^4 + 6/x^2 + 3) (-2/x^3)
gilded nova
yup, thats the way to do it👍
dapper crag
Thanks for your help