Find Value of k for Limit: x^3-6 / x^k+3

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SUMMARY

The limit of the expression (x^3 - 6) / (x^k + 3) as x approaches infinity exists when k is equal to 3. By multiplying both the numerator and denominator by 1/x^3, the expression simplifies to 1 / (x^(k-3) + 3/x^3). Analyzing the cases, when k > 3, the limit approaches 0; when k < 3, the limit approaches infinity; and when k = 3, the limit equals 1. Thus, the only value of k that allows the limit to exist is k = 3.

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Homework Statement



find the value of k such that the limit exists. lim xgoes to infinity (x^3-6)/(x^k+3).


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The Attempt at a Solution



I multiply both sides by 1/x^3 I get 1 in the numerator and x^k/x^3 in the denominator. I don't know what to next.
 
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x^k/x^3 is x^(k-3). Consider the cases of k>3, k<3 and k=3.
 

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