How do you calculate #log_2 128#?

1 Answer
Jun 11, 2016

#log_2 128 = 7#

Explanation:

There are 2 formats which are interchangeable:

Log form and index form.

#a^b = c " " rArr log_a c = b#

In log form, ask the question..."to what power must 2 be raised to get 128?"

Knowing the powers of 2 is a huge advantage.
#128 = 2^7#

#log_2 128 = 7#