How do you solve $log_x7 = 1$ ?

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Answer 1 · 2015-10-26T20:11:01

$x = 7$

$log_a(b) =ln(b)/ln(a)$

So

$log_x(7) = ln(7)/ln(x)$

$=> ln(7)/ln(x) = 1$

$=>ln(7) = ln(x)$

Taking exponentiel both side

$=>x = 7$

Answer 2 · 2015-10-26T20:20:08

x=7

Consider powers of 10
Picking one at random

$10^2 = 100$

If this were to be written as log base 10 it would be:

$log_10(100) = 2$

Following the same approach for your question but in you case we could reverse the process to get something we can work out.

so $log_x(7) = 1 " "->" " x^(1) = 7$

Anything raised to the power of one is its own value

So $x^1 = x = 7$

This means that if z is any number (technically you would have to say that $z in R$ but I would not wary about that!)

Then $log_z(z) = 1$

How do you solve log_x7 = 1log_x7 = 1?