Limit to Infinity: Is $$\lim_{{x}\to{\infty}} \sqrt{x^2 + 2x + 1} - x = 1?$$

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SUMMARY

The limit $$\lim_{{x}\to{\infty}} \sqrt{x^2 + 2x + 1} - x$$ evaluates to 1. This conclusion is reached by rewriting the expression under the square root as a perfect square, specifically $$(x + 1)^2$$. The calculation shows that as x approaches infinity, the expression simplifies correctly to yield the limit of 1, contrary to the initial assumption of 0.

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tmt1
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I have in my notes that $$\lim_{{x}\to{\infty}} \sqrt{x^2 + 2x + 1} - x = 1$$

Is this right? When I calculate it, I get 0, because the square root of infinity is infinity and then I subtract infinity which is 0.
 
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You can't legitimately subtract infinities...but what you can do is rewrite the radicand as a square...then the desired result is forthcoming. :D
 

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