Finding the limit of x/sqrt(x^2 + 1) as x--> +infty

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SUMMARY

The limit of the expression (x/sqrt(x^2 + 1)) as x approaches infinity is 1. To solve this, the correct approach involves simplifying the expression by dividing both the numerator and denominator by x, which leads to the limit being evaluated without the need for L'Hôpital's rule. The final simplification reveals that the limit can be easily computed as x approaches infinity, confirming the result of 1.

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Homework Statement



I need to find the limit of (x/sqrt(x^2 + 1)) as x goes to infinite for an infinite sequences problem.

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The Attempt at a Solution


I thought I would do L'H rule but I continually get infinite/infinite type does this mean it does not exist?
 
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Try simplifying the expression by dividing both the numerator and denominator by x (so overall you've just multiplied by x/x=1 and haven't changed the expression). You'll be left with something you can find the limit of without having to use L'Hopital's rule.
 
So I did that and I got 1 / [(x+1)/(x^2)]^(1/2)
 
Last edited:
Right, now simplify everything in the square root sign and you'll find that the equation reduces to something you can easily take the limit of as x-> infinity

Edit: By simplify I mean expand the fraction as two fractions over x^2. Also I believe that you mean \sqrt{\frac{x^2+1}{x^2}}
 
Last edited:
yes I get it now I messed up with one of the x's in the denominator not being squared thanks everyone
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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