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# Chain rule or product rule? watch

1. How would you differentiate y = 6x(1 + x^2 )^2

I'm not sure in what situation you use chain rule and in what situation you would use product rule?

If it was y = 6(1 + x^2 )^2
..could I use chain rule?
2. (Original post by Peanut247)
How would you differentiate y = 6x(1 + x^2 )^2

I'm not sure in what situation you use chain rule and in what situation you would use product rule?

If it was y = 6(1 + x^2 )^2
..could I use chain rule?
You would use both

Though, tbh, I would just multiply that out
3. (Original post by TenOfThem)
You would use both

Though, tbh, I would just multiply that out
What do you mean you would use both?
4. (Original post by Peanut247)
What do you mean you would use both?
You have a product so you need to use the product rule

One of the functions is a function of a function so that would need the chain rule
5. (Original post by Peanut247)
How would you differentiate y = 6x(1 + x^2 )^2

I'm not sure in what situation you use chain rule and in what situation you would use product rule?

If it was y = 6(1 + x^2 )^2
..could I use chain rule?
You can use whatever rule you like. requires first the use of linearity of the derivative, to obtain , then you could use chain to get .

Alternatively, you could use product: means .

(By the way, by chain rule. It doesn't help here, but some problems are made easier if you know that the function in question is the derivative of something.)
6. (Original post by Smaug123)
You can use whatever rule you like. requires first the use of linearity of the derivative, to obtain , then you could use chain to get .

Alternatively, you could use product: means .

(By the way, by chain rule. It doesn't help here, but some problems are made easier if you know that the function in question is the derivative of something.)
You seem to be differentiating a different question

Then you are referencing integration rules ... Why?
7. (Original post by Peanut247)
How would you differentiate y = 6x(1 + x^2 )^2

I'm not sure in what situation you use chain rule and in what situation you would use product rule?

If it was y = 6(1 + x^2 )^2
..could I use chain rule?
Fairly sure you can use just use chain for the second one
8. (Original post by TenOfThem)
You seem to be differentiating a different question

Then you are referencing integration rules ... Why?

Also, he merely made a comment on the integration bit...noting that in this particular case it didnt help but can sometimes be useful in such a problem.
9. (Original post by Smaug123)
You can use whatever rule you like. requires first the use of linearity of the derivative, to obtain , then you could use chain to get .

Alternatively, you could use product: means .

(By the way, by chain rule. It doesn't help here, but some problems are made easier if you know that the function in question is the derivative of something.)
But when I differentiate y= 6x(1+ x^2)^2 using chain rule and the product rule I get different answers..
10. (Original post by newblood)

Also, he merely made a comment on the integration bit...noting that in this particular case it didnt help but can sometimes be useful in such a problem.
If you say so
11. (Original post by Peanut247)
But when I differentiate y= 6x(1+ x^2)^2 using chain rule and the product rule I get different answers..
Once again ... You need to use both but it would be better to multiply it out

Can I check .... Since I have been told that I have misread

You are differentiating 6x(1+x^2)^2 and none of those x are a multiplication sign ... Or ?
12. (Original post by TenOfThem)
If you say so
There is no need for attitude. Please try to be more helpful on the maths forum in future
13. (Original post by newblood)
There is no need for attitude. Please try to be more helpful on the maths forum in future
No attitude here ... We clearly have a different understanding of this thread ... As for your second point ... Are you serious
14. (Original post by TenOfThem)
Once again ... You need to use both but it would be better to multiply it out

Can I check .... Since I have been told that I have misread

You are differentiating 6x(1+x^2)^2 and none of those x are a multiplication sign ... Or ?
Yes none of them are multiplication signs sorry.
So do you mean you would use chain regarding (1+x^2)^2 within the product rule?
15. (Original post by Peanut247)
Yes none of them are multiplication signs sorry.
So do you mean you would use chain regarding (1+x^2)^2 within the product rule?
Exactly
16. (Original post by TenOfThem)
No attitude here ... We clearly have a different understanding of this thread ... As for your second point ... Are you serious
Please lose the attitude. If you have nothing useful to contribute to help OP, then please dont at all
17. (Original post by newblood)
Please lose the attitude. If you have nothing useful to contribute to help OP, then please dont at all
I am not sure what your issue is

If you read this thread you will see that my posts have led to the OP understanding how to solve the question

You posts, on the other hand have simply been aimed at criticising me

So ...
18. (Original post by TenOfThem)
Exactly
Ah so you can't just use chain rule by itself to differentiate it... Thank you
I was trying to do the "quick chain rule" method
19. (Original post by Peanut247)
Ah so you can't just use chain rule by itself to differentiate it... Thank you
That is correct ... Chain rule is used when we have a function of a function

The 6x was separate to this and needed the product rule
20. (Original post by newblood)
There is no need for attitude. Please try to be more helpful on the maths forum in future
(Psst - TenOfThem is one of the more prolific helpers on this thread )

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