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PlzhelpHow do i do this step by step logarithmic equation
ln(x2+x+5)=ln( - 3x+1)

User ASemy
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1 Answer

5 votes

\ln(x^2+x+5)=\ln(-3x+1)

First note that for both sides to be defined, we require
x^2+x+5>0 and
-3x+1>0. The first condition is met for all
x, and the other requires that
x<\frac13.

Now,


e^(\ln(x^2+x+5))=e^(\ln(-3x+1))

x^2+x+5=-3x+1

x^2+4x+4=0

(x+2)^2=0

x=-2

Since
-2<\frac13, this is the only solution.
User Carl Suster
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