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# How do you differentiate- watch

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1. ((a^2-a+0.5)^0.5)/3?

I try using the chain rule, but just end up with a mess. Do I ignore the /e when differentiating the top?
2. Is that ? or
3. (Original post by JumpingJonny)
Is that ? or
The latter. It's everything divided by 3.
4. You can take out the 1/3 as a constant:

Then use the chain rule with the substitution

5. Let

Note that

Well, you can find and
6. (Original post by EierVonSatan)
You can take out the 1/3 as a constant:

Then use the chain rule with the substitution
This, I had to go get dinner so was beaten to it...again
7. Should I get

(2a-1)/(6(a^2-1+0.5)^0.5)

??

8. Im not sure if this is right but if it is, can you just leave it in this form?:

9. (Original post by samir12)

Correct me if I'm wrong but I don't think you can expand the bracket in the last step...?
10. (Original post by Hippysnake)
Should I get

(2a-1)/(6(a^2-a+0.5)^0.5)

??
I assume thats a typo, so yes
11. Well , if that counts for anything. If you're differentiating with respect to , on the other hand, then the chain rule works. Use and it's fairly straightforward.

(Original post by Hippysnake)
Correct me if I'm wrong but I don't think you can expand the bracket in the last step...?
You're right; it should have been
12. (Original post by Hippysnake)
Correct me if I'm wrong but I don't think you can expand the bracket in the last step...?
You can't.
13. (Original post by EierVonSatan)
I assume thats a typo, so yes
It's not a typo...I don't think so anyway

Eitherway, now I'm stuck on this step-

-5a^(-6) + (^that equation) = 0

Looks mighty...

14. I am sorry the typing is so big. I would prefer it were smaller.
15. (Original post by Hippysnake)
It's not a typo...I don't think so anyway
So you did mean ?
16. (Original post by EierVonSatan)
So you did mean ?
no.....?
17. (Original post by EierVonSatan)
So you did mean ?
Why would there be a 1 there? There shouldn't be (and even if there was, -1 + 0.5 = -0.5).
18. anyway guys, could you help with the next part?

-5a^(-6) + ^^that equation = 0?
19. (Original post by Hippysnake)
Should I get

(2a-1)/(6(a^2-1+0.5)^0.5)

??
(Original post by EierVonSatan)
(Original post by Hippysnake)
Should I get

(2a-1)/(6(a^2-a+0.5)^0.5)

??
I assume thats a typo, so yes
(Original post by Hippysnake)
It's not a typo...I don't think so anyway
So it was a typo
20. (Original post by Hippysnake)
anyway guys, could you help with the next part?

-5a^(-6) + ^^that equation = 0?
Which equation? The original one, or the differentiated one? Either way it seems like a fairly ridiculous equation to have to solve. You'd have to move the to the other side, square both sides and multiply through by to start with... and that would be near impossible to solve without iteration or Wolfram|Alpha.

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