The equation `log_2 x - log_ 4 x = 2` has to be solved for
x.
First convert all the logarithm to a common base. As the
numbers here are 2 and powers to two we use the base 2. Use the following property
useful when changing the base of logarithms.
`(log_b x) =
(log_n x)/(log_n b)`
`log_2 x - log_ 4 x =
2`
`log_2 x - (log_2 x)/(log_2 4) =
2`
`log_2 x - (log_2 x)/(log_2 2^2) =
2`
use the property `log a^b = b*log
a`
`log_2 x - (log_2 x)/(2*log_2 2) =
2`
Now `log_b b = 1`
`log_2 x
- (log_2 x)/(2*1) = 2`
`(1/2)*log_2 x = 2`
`log_2 x = 4`
If `log_b x =
y` , `x = b^y`
`x = 4^2`
x =
16
The required solution is x = 16
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