Question #f182a

1 Answer
Nov 29, 2017

#x# can be equal to any real number greater than #0#.

Explanation:

We can prove that the expressions are equal, if we start with #log_2(x)#, we can apply the logarithm rule which says:
#log_a(b)=log_x(b)/log_x(a)#, where #log_x# can be any logarithm you choose.

Let's pick #log_16#:
#log_2(x)=log_16(x)/log_16(2)#

Since #log_16(2)=1/4#, we can simplify:
#log_16(x)/log_16(2)=log_16(x)/(1/4)=log_16(x)*4/1=4log_16(x)#

So we have proven that #log_2(x)=4log_16(x)# where x is a real number greater than zero (because otherwise the #log# functions aren't defined).