Finding Limit x -> Infinity of y = 2x^2/(a+2x)

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I need to find the limit x -> infinity of the following:

y = x ( (2x/a) / (1 + (2x/a)) )

Simplifying..

y = x ( (2x/a) / ((a + 2x)/a) )

y = x ( 2x / (a + 2x) )

y = 2x^2 / (a + 2x)

Is this even right in the first place? because I have no idea how to evaluate the lim x -> infinity.
 
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