Simple calc limit problem help

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I'm in Calc I and have run into a probably simple problem I can use guidance on.

Evaluate the following Limit

lim x -> -1 [(2x-1)^2 - 9] / [x+1]

Its been a few years since pre-calc and I'm drawing a blank on how to proceed on this problem. Thanks for any help offered!
 
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Try to factor (2x-1)^2-9 and see if x+1 is a factor. I think it is.
 
That's what it was, thanks!

How about this one?? The book has the answer as -1

lim x -> b [(x-b)^50 - x + b] / [x - b]
 
Matus1976 said:
That's what it was, thanks!

How about this one?? The book has the answer as -1

lim x -> b [(x-b)^50 - x + b] / [x - b]

Write the numerator as (x-b)^50-(x-b). It is divisible by (x-b), right?
 
Dick said:
Write the numerator as (x-b)^50-(x-b). It is divisible by (x-b), right?

Yeah that did it, thanks again! I didn't think to factor the -1 out.
 
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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