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# Chain rule help? watch

1. I have to use the chain rule to differentiate y=sin(t^2+9t+11)

Is it just U=(t^2+9t+11) and Y=sin(U) ??
Is this right? Why do i even have to use the chain rule for this case?
2. (Original post by ErniePicks)
I have to use the chain rule to differentiate y=sin(t^2+9t+11)

Is it just U=(t^2+9t+11) and Y=sin(U) ??
Is this right? Why do i even have to use the chain rule for this case?
Yes, that's correct, then we have that
3. Yeah that's correct, why would you not use the chain rule? It is a function in a function.
4. (Original post by Dinasaurus)
Yeah that's correct, why would you not use the chain rule? It is a function in a function.
I got 2t+9(cos(t^2+9t+11)) as the answer though, it doesn't look right...
5. (Original post by ErniePicks)
I got 2t+9(cos(t^2+9t+11)) as the answer though, it doesn't look right...
Most chain rule answers look messier than the original function given.
6. (Original post by ErniePicks)
I got 2t+9(cos(t^2+9t+11)) as the answer though, it doesn't look right...
If you mean (if you mean the former) then you're correct, if you mean the latter, then you're wrong.
7. you are good human beings
8. (Original post by ErniePicks)
I got (2t+9)(cos(t^2+9t+11)) as the answer though, it doesn't look right...
just remember to bracket that term but other than that its perfect

doesnt look "right" because sin(t^2+9t+11) is a weird looking function

Edit: i think there is an echo whoops

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