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# Quick question quick answer Watch

1. Find dx
dy

y = 2X^3 - 3X^2 + 4X - 6

Also, am I the only one who really enjoys surds ?

Yes I know these aren't surds, inb4 so [email protected] says it. Thanks for the help, will loiter to pay it forward.
2. (Original post by HanSoloLuck)
Find dx
dy

y = 2X^3 - 3X^2 + 4X - 6

Also, am I the only one who really enjoys surds ?

Yes I know these aren't surds, inb4 so [email protected] says it. Thanks for the help, will loiter to pay it forward.
What's the issue? It's a simple case of differentiating each term carefully by using the rule that differentiating ax^n gives anx^(n-1).
3. Firstly I think you mean dy/dx

and secondly like the person above me said what's the issue ?

dy/dx = 6X^2 - 6X + 4
4. (Original post by Shoot)
Firstly I think you mean dy/dx

and secondly like the person above me said what's the issue ?

dy/dx = 6X^2 - 6X + 4
Nope, i don't get it. I know it's something incredibly dumb that I'm missing, but, I can no brain that at the moment.
5. (Original post by HanSoloLuck)
Nope, i don't get it. I know it's something incredibly dumb that I'm missing, but, I can no brain that at the moment.
Saying "i don't get it" is extremely useless. What particular bit don't you get? What's the issue? What have you tried?
6. (Original post by HanSoloLuck)
Nope, i don't get it. I know it's something incredibly dumb that I'm missing, but, I can no brain that at the moment.
Don't worry man I got you on this,

basically what I did was the differentiation rule ( you can take all the values out separately if it makes it easier for you to understand)

So the f(x) = 2X^3 - 3X^2 + 4X - 6

So you have the value of 2X^3, - 3X^2 , 4X and - 6

Now what you basically do is times the indices to the coefficient

so in this case I did 2 x 3, 3 x 2 and 4 x 1 ( I ignore the 6 as it doesn't have a variable and isn't a coefficient )

Then once I do that I subtract the indices by -1 so the ^3 becomes ^2, the ^2 (on 3X) becomes ^1 (so just X) and the X is removed from the 4X as it was basically (4X^1)

So my answer then is dy/dx = dy/dx = 6X^2 - 6X + 4
7. (Original post by Zacken)
Saying "i don't get it" is extremely useless. What particular bit don't you get? What's the issue? What have you tried?
I like your enthusiasm to want to help, it's a little creepy but kinda nice. Didn't realize what it was asking me/was trying to do something else entirely without realizing.

(Original post by Shoot)
Don't worry man I got you on this,

basically what I did was the differentiation rule ( you can take all the values out separately if it makes it easier for you to understand)

So the f(x) = 2X^3 - 3X^2 + 4X - 6

So you have the value of 2X^3, - 3X^2 , 4X and - 6

Now what you basically do is times the indices to the coefficient

so in this case I did 2 x 3, 3 x 2 and 4 x 1 ( I ignore the 6 as it doesn't have a variable and isn't a coefficient )

Then once I do that I subtract the indices by -1 so the ^3 becomes ^2, the ^2 (on 3X) becomes ^1 (so just X) and the X is removed from the 4X as it was basically (4X^1)

So my answer then is dy/dx = dy/dx = 6X^2 - 6X + 4
Yep thanks, simple to do, as said above, I was trying to do something else entirely. I'll bring my crayons to the exam I guess, wont even use them to draw, just jam them up my nose........ over tired.

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