Limits...what am I doing wrong ? (Without hopital)

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SUMMARY

The limit as x approaches positive infinity for the expression sqrt(3x^5-2x) - sqrt(3x^5-7x) can be simplified by rationalizing the numerator, resulting in (5x) / [sqrt(3x^5-2x) + sqrt(3x^5-7x)]. The correct approach involves factoring out x^5 from each radical, allowing the expression to be simplified to (5x) / [x^(5/2)(sqrt(3 - 2/x^4) + sqrt(3 - 7/x^4))]. Dividing by x^5 is unnecessary and incorrect in this context, as it complicates the limit evaluation.

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Homework Statement



Limx--->positive infinity sqrt(3x^5-2x) - sqrt(3x^5-7x)

Homework Equations

The Attempt at a Solution


The first thing I did was rationalize. I got (5x)/ [ sqrt(3x^5-2x) + sqrt(3x^5-7x)]. Then I divided the top and bottom by x^5 but this is where I feel like I am doing something wrong. But I don't know what. Am I even supposed to divide by x^5 ? Because the other problems I've solved so far have been with an x^2.
 
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AlexandraMarie112 said:

Homework Statement



Limx--->positive infinity sqrt(3x^5-2x) - sqrt(3x^5-7x)

Homework Equations

The Attempt at a Solution


The first thing I did was rationalize. I got (5x)/ [ sqrt(3x^5-2x) + sqrt(3x^5-7x)]. Then I divided the top and bottom by x^5 but this is where I feel like I am doing something wrong. But I don't know what. Am I even supposed to divide by x^5 ? Because the other problems I've solved so far have been with an x^2.
Factor x5 out of each radical, and bring each out of its radical as x5/2.
 
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What happens, if you simply divide by / cancel x?
 

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