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

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The limit $$\lim_{{x}\to{\infty}} \sqrt{x^2 + 2x + 1} - x$$ is indeed equal to 1. Initial calculations may suggest it equals 0 due to the behavior of infinity, but this approach overlooks the need to simplify the expression. By rewriting the radicand as a perfect square, the limit can be accurately evaluated. The correct method reveals that the limit approaches 1 as x approaches infinity. Thus, the assertion that the limit equals 1 is confirmed.
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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
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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