Why is lim x->infinity of 2^-x = 0?

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Homework Statement



Hey guys, just getting into the exponential functions and got stuck on something. Can someone please explain this for me?

Find lim x-->∞ (2^-x)

The answer is 0

Why? I don't quite understand.

I know that something like 2^-x would just be 1/2^x

?


Homework Equations





The Attempt at a Solution

 
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2^-x = 1/(2^x)

As x tends to infinity, what happens to the denominator, (2^x)?
 

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