Lnx-ln5=10?

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Answer 1 · 2018-02-13T14:46:44

$x = 50$ $x =50$

We have:

$ln x - ln 5 = ln 10$ $ln x -ln 5 = ln 10$

Using the result lnA=lnB=ln(A/B)# we can write:

$ln (\frac{x}{5}) = ln 10$ $ln(x/5) = ln10$

The logarithm is a $1 : 1$ $1:1$ function so:

$ln A = ln B \Leftrightarrow A = B$ $ln A= ln B iff A=B$

And so we have:

$\frac{x}{5} = 10 \Rightarrow x = 50$ $x/5 = 10 => x =50$