We'll set the constraints of existence of
logarithms:
x+2>0
x>-2
3x>0
x>0
The
common interval of admissible values for x is
(0,+inf.).
Now,we'll could solve the equation in this way,
also:
We'll subtract ln (x+2) both
sides:
- ln 3x = ln 5 - ln
(x+2)
We'll multiply by -1 both
sides:
ln 3x = ln (x+2) - ln
5
We'll apply the quotient property of
logarithms:
ln 3x = ln
[(x+2)/5]
Because the bases of logarithms are matching,
we'll apply the one to one property:
3x =
(x+2)/5
We'll cross
multiply;
15x = x+2
We'll
subtract x both sides:
14x =
2
We'll divide by 14:
x =
2/14
x = 1/7>0
Since
the value for x is in the interval of admissible values, the solution is
valid.
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