Why does 2^(-log₂(x)) simplify to 1/x?

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repugno
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2^(-log2(x)) It reads, 2 to the power of -log base2 x

The problem is that I don't understand why this can also be written as x^-1

For some reason the base and the log2 cancel out. Can anyone explain to me why this happens, please?

1/2^(log2(x)) = 1/x
 
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-log2(x)=log2(x^(-1)),
by the rule for logarithms:
blog(a)=log(a^(b))
 
Or you could use that:

[tex]a^{bc} = \left(a^c \right)^b[/tex]

As [itex]- \log_2 x = (-1) \log_2 x[/itex]