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# differentiation confused? watch

1. If you do dy/dx of x^4/4 + 32/x^2 does it become dy/dx of 4x^4-1 + 32x-2 ?
2. X^3 -64x^-3 is what you should get, remember the power of X is multiplied by the coefficient and and the new power is n-1 such that: if y = x^n
Dy/dx = nx^n-1

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3. (Original post by kiiten)
If you do dy/dx of x^4/4 + 32/x^2 does it become dy/dx of 4x^4-1 + 32x-2 ?
To find use the general rule;

if then

For the second term dont forget to use the indice rule

Edit: damn i am too slow with latex
4. (Original post by DylanJ42)
To find use the general rule;

if then

For the second term dont forget to use the indice rule

Edit: damn i am too slow with latex
I was actually thinking how much nicer it would look with latex

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5. (Original post by kiiten)
If you do dy/dx of x^4/4 + 32/x^2 does it become dy/dx of 4x^4-1 + 32x-2 ?
You can't do dy/dx of some function or expression. You do d/dx of something. If you have y=f(x) and differentiate both sides wrt x, you get dy/dx=f'(x).
6. (Original post by drandy76)
I was actually thinking how much nicer it would look with latex

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and im thinking of how much quicker the reply would be without latex

we can never win
7. Think the best method is a quick post before editing to put it in latex, best of both worlds

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8. I try to do things in LaTeX first. I find it hard to understand things not formatted nicely. But yeah, it is slow. I need to practice more so I don't have to keep looking at the wiki page.
9. (Original post by drandy76)
Think the best method is a quick post before editing to put it in latex, best of both worlds

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Nah, just keep using LaTeX, gets faster than not using LaTeX after a while and and some practice.
10. (Original post by DylanJ42)
To find use the general rule;

if then

For the second term dont forget to use the indice rule

Edit: damn i am too slow with latex
So for x^4/4 using the indice rule do you get 4x^3 which is differentiated to get 12x^2 ?
11. (Original post by kiiten)
So for x^4/4 using the indice rule do you get 4x^3 which is differentiated to get 12x^2 ?
you have which can be rewritten as

ignore the 1/4 for now. can you differentiate x^4 for me?
12. (Original post by kiiten)
So for x^4/4 using the indice rule do you get 4x^3 which is differentiated to get 12x^2 ?
Differentiating is a liner operation. i.e:

Use this in conjunction with DylanJ's post above.
13. (Original post by Zacken)
Nah, just keep using LaTeX, gets faster than not using LaTeX after a while and and some practice.
This, I always use LaTeX and I've become quite good at it now. I can type up things quite fast.
14. (Original post by edothero)
This, I always use LaTeX and I've become quite good at it now. I can type up things quite fast.
masterrace
15. (Original post by Zacken)
masterrace
I'd rep but according to TSR, you've been stealing quite a lot of them recently
16. (Original post by edothero)
I'd rep but according to TSR, you've been stealing quite a lot of them recently
Have a rep from me.
17. (Original post by DylanJ42)
you have which can be rewritten as

ignore the 1/4 for now. can you differentiate x^4 for me?
Ahh i see - i remember this method now. Do you get x^3 ?
18. (Original post by kiiten)
Ahh i see - i remember this method now. Do you get x^3 ?

in this case

So you are right, it would be but you're missing something else!
19. (Original post by edothero)

in this case

So you are right, it would be but you're missing something else!
Missing something? I only differentiated the first term (x^4/4) to get x^3
20. (Original post by kiiten)
Missing something? I only differentiated the first term (x^4/4) to get x^3
Oh I see, no you're correct! I thought you meant you got when you differentiated

My bad!

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