Finding the value of constants in f(x) as x->0

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I'm not looking for the complete answer (from what I've read in the intro posts, you won't/shouldn't give it to me anyways)... I just need to figure out where to start. This is my first time taking calc, and I'm pretty lost. Thanks in advance.

Homework Statement



Find the values of the constants a and b such that

lim (x\rightarrow0) [ ( \sqrt{a+bx} - \sqrt{3} ) / x ] = \sqrt{3}

The Attempt at a Solution



I've attempted to solve it a couple of ways in an algebraic style, but the fact that there are three 'variables' has me stumped. I also tried using the limit property that states the limit of h(x)=f(x)/g(x) as x->c is L/K (I hope I got that right.. hah.) but the fact that K ends up being zero screws that up...

I'm just completely lost as to where I need to start the problem. I don't know if I should be solving for a variable, doing trial-and-error stuff, using some kind of limit property, etc.
 
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Let
f(x)=\frac{\sqrt{a+b\,x}-\sqrt3}{x}=\frac{g(x)}{x}
and solve for g(x)

What's the limit \lim_{x\to 0}g(x) ?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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