Question #a2dcd

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Answer 1 · 2016-02-27T20:29:31

If: $log_y(x) = 1$ => then: $x=y$
but if: $log_y(1)=x$ => then: $x=0$

Definition of logarithm:
For $x>0$
if: $log_a(x)=y$
then: $x=a^y$

For $x<=0$ :
$log_a(x)$ is "Undefined"

Answer 2 · 2016-02-27T20:38:44

$x=10$
(what you "knew" was incorrect)

Two points:
[1] $color(white)("XXX")$ the default base for $log$ is $10$ : $log x$ means $log_10 x$
[2] $color(white)("XXX")log_b a = k hArr b^k=a$

From [1]
$color(white)("XXX")log x =1$ is the same as $log_10 x = 1$

From [2]
$color(white)("XXX")log_10 x = 1 hArr 10^1 = x$

Therefore
$color(white)("XXX")x=10^1 = 10$