# Homework Help: Evaluate the Limit (just confirmation)

1. Mar 20, 2013

### NATURE.M

1. The problem statement, all variables and given/known data

lim (cubicsquareroot(x) - 2)/(x-8)
x→8

2. Relevant equations

3. The attempt at a solution

I obtained 1/12 as my final answer, after changing the variable since its in indeterminate form.
..let p=cubicsquareroot(x), then as x→8, p→2
then, p^3=x

Using this logic I obtained 1/12.

Is this correct ?

2. Mar 20, 2013

### PrashntS

Precisely, Although It'd be nicer if you had done some substitutions.. Yeah is correct!

3. Mar 20, 2013

### PrashntS

My bad! you have! And when you reach L'Hopital's rule, revisit these questions..

4. Mar 20, 2013

### SammyS

Staff Emeritus
What's a "cubicsquareroot" ?

5. Mar 20, 2013

### PrashntS

Assumed he meant x^(1/3) *kids today*

6. Mar 20, 2013

### NATURE.M

lol Yeah I mean't x^(1/3). And thanks.

7. Mar 20, 2013

### Staff: Mentor

L' Hopital's Rule is not needed in this problem.

The OP apparently revised the original problem to this form:
$$\lim_{p \to 2} \frac{p - 2}{p^3 - 8}$$

and then factored the denominator to (p - 2)(p2 + 2p + 4), and then took the limit.