# Homework Help: Confusing Limits

1. Jun 19, 2011

### BloodyFrozen

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

1. limh->0 (sqrt(a+h)-sqrt(a))/h
2. limx->1 (1-sqrt(x))/(1-x)

2. Relevant equations

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3. The attempt at a solution

I tried conjugate, etc., but couldn't solve it without L'H's Rule.

2. Jun 19, 2011

### vela

Staff Emeritus
Using the conjugate will work. What did you get when you tried that?

3. Jun 19, 2011

### BloodyFrozen

Thanks I got 1/(2)for one and 1/2 for number 2

Last edited: Jun 19, 2011
4. Jun 19, 2011

### Char. Limit

For the second one, try factoring the numerator like so:

$$1 - x =\left(1 - \sqrt{x}\right)\left(1 + \sqrt{x}\right)$$

The solution should then become obvious.

EDIT: And for the first one, multiplying by the conjugate of the numerator is what you need to do.

5. Jun 20, 2011

### BloodyFrozen

Thanks guys, got them.

Ignore my comment above this.

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