How do you solve #8 log_2 2-2log_2 8#?

1 Answer
Nov 13, 2015

#8log_2 2 - 2 log_2 8 = 2#

Explanation:

Evaluating #log_2 2# is equivalent to asking
#color(white)("XXX")#"For what value #p=log_2 2# is #2^p = 2#?"
The obvious answer is #log_2 2 = p = 1#

Similarly, evaluating #log_2 8# is equivalent to asking
#color(white)("XXX")#"For what value #q=log_2 8# is #2^q=8#?
with an obvious answer #log_2 8 = q = 3#

So
#color(white)("XXX")8log_2 2 - 2log_2 8#
#color(white)("XXXXXX")=8xx1 - 2xx3#
#color(white)("XXXXXX")=2#