MHB How Do You Determine the Range of the Function y = 2x/(x - 1) Through Graphing?

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To determine the range of the function y = 2x/(x - 1) through graphing, the function can be rewritten to identify its behavior. The transformation shows a horizontal asymptote at y = 2, indicating that the range excludes this value. Consequently, the range is defined as (-∞, 2) ∪ (2, ∞). The graph resembles y = 1/x, vertically stretched by a factor of 2 and shifted right and up, but these transformations do not change the overall range. Understanding these characteristics allows for accurate identification of the function's range.
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Find the range of y = 2x/(x - 1) by graphing?

What are the steps? How is this done?
 
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I would write:

$$y=\frac{2x}{x-1}=\frac{2x-2+2}{x-1}=\frac{2(x-1)+2}{x-1}=2+\frac{2}{x-1}$$

We see this will have a horizontal asymptote at $y=2$, and so the range must be:

$$(-\infty,2)\,\cup\,(2,\infty)$$

We know this will have a graph that is the same as $$y=\frac{1}{x}$$, but vertically stretched by a factor of 2 and translated one unit to the right, neither of which affect the range. It will also be translated 2 units up, which will affect the range by moving the horizontal asymptote up 2 units.
 
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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