Don't understand how to simplify this limit

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SUMMARY

The discussion centers on simplifying the limit as x approaches -1 for the expression (x^(1/3) + 1) / (x + 1). The correct approach involves recognizing that the expression can be rewritten using the substitution u = x^(1/3), leading to the limit of (u + 1) / (u^3 + 1). Factoring u^3 + 1 as (u + 1)(u^2 - u + 1) allows for cancellation of the common factor, simplifying the limit evaluation process.

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Homework Statement



lim
x->-1 x^1/3 + 1 / x + 1 = x^1/3 + 1 / x + 1 ((x^2/3 - x^1/3 + 1) / (x^2/3 - x^1/3 + 1))

= x + 1 / (x + 1)(x^2/3 - x^1/3 + 1)

cancel out and done


I don't understand how to know what reciprocal to multiply in cases like these to make it work.
Please help.
 
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Your formatting is horrible. Use more parentheses, ok? I think you mean limit x->(-1) of (x^(1/3)+1)/(x+1). It might be a little clearer if you change variables first and let u=x^(1/3). So u->(-1) also and now your expression is (u+1)/(u^3+1). Can you factor (u^3+1)=(u+1)*(something)? Use polynomial division to divide u^3+1 by u+1 if you don't know the answer.
 

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