How do you evaluate $log_2 4 - log_2 16$ ?

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Answer 1 · 2015-07-09T21:12:05

Since $4=2^2and 16=2^4$ we can rewrite:

$=log_2 2^2-log_2 2^4$

Exponent rule:
$=2*log_2 2-4*log_2 2$

Since $log_b b=1$ for any $b->log_2 2=1$
$=2*1-4*1=-2$

How do you evaluate log_2 4 - log_2 16log_2 4 - log_2 16?