## Study23 3 years ago I'm stuck on this (Chain Rule!!) Differentiation problem: $$\ \Huge \frac{1}{(t^4+1)^3} .$$

1. Dido525

I would make it a negative exponent.

2. Dido525

|dw:1352344215249:dw|

3. Dido525

Can you do it now?

4. Study23

I'll give it a try. Thanks for the hint, @Dido525!

5. Dido525

Welcome :) .

6. Dido525

Let me know what you get.

7. Study23

$$\ \Huge \text{Okay. We're both 63 :)}$$

8. Dido525

63?

9. Study23

$$\ \text{Not age, of course (though I have no way of knowing...); I was referring to SmartScore.}$$

10. Study23

SmartScore*

11. Dido525

Ohh...

12. Study23

$$\ \large \text{Okay, so I got: }$$ $$\ \Huge -3(t^4+1)^{-4}+4t^3,$$ $$\ \Large\text{Is that correct?}$$

13. Babyslapmafro

Close, but that is not correct.

14. Study23

@Babyslapmafro $$\ \Large\text{Where did I go wrong?}$$

15. Babyslapmafro

You must multiply the derivative of the outside by the derivative of the inside, you added the two.

16. Dido525

17. Study23

$$\ \Huge \text{?}$$

18. Study23

$$\ \Huge \text{Where?}$$

19. Babyslapmafro

You must multiply the derivative of the quantity (t^4+1) to the derivative of the outside function.

20. Dido525

|dw:1352344924295:dw|

21. Study23

Oh! Wrong sign. Thanks for pointing that out. The answers in the book in the back say this is the correct answer (with a multiplication sign). Thanks @Dido525 and @Babyslapmafro!

22. Dido525

Welcome :) .

23. Babyslapmafro

$-\frac{ 12t^3 }{ (t^4+1)^4 }$

24. Babyslapmafro

That is the answer in a more simplified "cleaner" format.