How do you solve $Ln (x-1) + ln (x+2) = 1$ ?

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Answer 1 · 2016-06-20T19:17:38

$x = 1/2 (-1 +sqrt[9 + 4 e]) = 1.72896$

$Ln (x-1) + ln (x+2) = 1->Ln(x-1)(x+2)=Ln e$

$(x-1)(x+2)-e=0$

Solving for $x$

$x = 1/2 (-1 pm sqrt[9 + 4 e]) = {-2.72896, 1.72896}$

Now, substituting those values in $(x-1)$ and $(x+2)$ keeping in mind that both must be positive, we get at the solution.

$x = 1/2 (-1 +sqrt[9 + 4 e]) = 1.72896$

How do you solve Ln (x-1) + ln (x+2) = 1Ln (x-1) + ln (x+2) = 1?