I am having trouble finding the derivative of cubed root of x using only limits. I know it is easy to use chain rule but I cannot use that yet.

- stapel_eliz
**Posts:**1738**Joined:**Mon Dec 08, 2008 4:22 pm-
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I'm sorry, I meant the cube root of x. as in cuberoot(x).

So far a tried finding the derivative with a limit as h approaches 0

lim h-->0[(cuberoot(a+h) - cuberoot(a)) / ((a+h) - a)]

With this, I always end up with an indeterminate form.

So far a tried finding the derivative with a limit as h approaches 0

lim h-->0[(cuberoot(a+h) - cuberoot(a)) / ((a+h) - a)]

With this, I always end up with an indeterminate form.

- Martingale
**Posts:**350**Joined:**Mon Mar 30, 2009 1:30 pm**Location:**USA-
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Andromeda wrote:I'm sorry, I meant the cube root of x. as in cuberoot(x).

So far a tried finding the derivative with a limit as h approaches 0

lim h-->0[(cuberoot(a+h) - cuberoot(a)) / ((a+h) - a)]

With this, I always end up with an indeterminate form.

use the fact that

Martingale wrote:Andromeda wrote:I'm sorry, I meant the cube root of x. as in cuberoot(x).

So far a tried finding the derivative with a limit as h approaches 0

lim h-->0[(cuberoot(a+h) - cuberoot(a)) / ((a+h) - a)]

With this, I always end up with an indeterminate form.

use the fact that

How would that work since and are not cubed numbers?

- Martingale
**Posts:**350**Joined:**Mon Mar 30, 2009 1:30 pm**Location:**USA-
**Contact:**

Andromeda wrote:Martingale wrote:Andromeda wrote:I'm sorry, I meant the cube root of x. as in cuberoot(x).

So far a tried finding the derivative with a limit as h approaches 0

lim h-->0[(cuberoot(a+h) - cuberoot(a)) / ((a+h) - a)]

With this, I always end up with an indeterminate form.

use the fact that

How would that work since and are not cubed numbers?

let and