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

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Answer 1 · 2016-12-27T17:46:32

$x = -1 + sqrt (1 + e)$

$ln a + ln b = ln ab ; ln(exp(x)) = x$

$ln x(x + 2) = ln (exp 1)$

$x(x + 2) = e$

$x^2 + 2x - e = 0$

$Delta = 4 + 4e$

$x = (-2 ± 2 sqrt (1 + e))/2$

$x = -1 ± sqrt (1 + e)$

$x = -1 ± 1,9282846855324670226473240752689...$

But we can't extract LN(negative number)

$x > 0$

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