We'll impose constraints of existence of
logarithms:
x>0
1-2x>0
-2x>-1
2x<1
x<1/2
The
interval of admissible values of x is (0 , 1/2).
5 log x -
log x^3 = log ( 1-2x)
We'll use power property of
logarithms for the first term:
5 log x = log
x^5
log x^5- log x^3 = log (
1-2x)
We'll add log x^3 both
sides:
log x^5 = log ( 1-2x) + log
x^3
We'll use the product property
of logarithms:
log a + log b = log
a*b
We'll put a=( 1-2x) and
b=x^3
log ( 1-2x) + log x^3 = log
x^3*(1-2x)
The equation will
become:
log x^5 = log
x^3*(1-2x)
Since the bases are matching, we'll use one to
one property:
x^5 =
x^3*(1-2x)
We'll divide by
x^3:
x^2 = 1 - 2x
We'll
subtract 1-2x:
x^2 + 2x - 1 =
0
x1 = [4-sqrt(4+4)]/2
x1 =
(4-2sqrt2)/2
x1 =
2-sqrt2
x2=2+sqrt2
Since
neither of x values belong to the interval of admissible values for x, the equation has
no solutions.
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