Question on lim x→1 (x − 5) / (x^2 + 2x − 4) ?

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Homework Statement



Determine whether the statement is true or false. lim x→1 (x − 5) / (x^2 + 2x − 4) = lim x→1 (x − 5) / lim x→1 (x^2 + 2x − 4)?

Homework Equations


[/B]

The Attempt at a Solution


I know that the right side of this equation and the left side have to equal each other in order for this to be true. On the right hand side the answer is 4. I don't know how to solve the left hand side because (x^2 + 2x − 4) cannot be factored.
 
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alaa amed said:

Homework Statement



Determine whether the statement is true or false. lim x→1 (x − 5) / (x^2 + 2x − 4) = lim x→1 (x − 5) / lim x→1 (x^2 + 2x − 4)?

Homework Equations


[/B]

The Attempt at a Solution


I know that the right side of this equation and the left side have to equal each other in order for this to be true. On the right hand side the answer is 4. I don't know how to solve the left hand side because (x^2 + 2x − 4) cannot be factored.
That's irrelevant. Can the limit of the LHS expression be evaluated without factoring the quadratic?
 
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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