We'll take logarithms both
sides:
log3 [x^(1+log3 x)] = log3
(9x^2)
We'll apply the power rule to the left
side:
(1+log3 x)*(log3 x) = log3
(9x^2)
We'll apply the product rule to the right
side:
(1+log3 x)*(log3 x) = log3 9 + log3
(x^2)
We'll remove the
brackets:
log3 x + (log3 x)^2 = 2 + 2log3
x
We'll move all terms to one
side:
(log3 x)^2 + log3 x - 2log3 x - 2 =
0
We'll combine like
terms:
(log3 x)^2 - log3 x - 2 =
0
We'll note log3 x = t
t^2 -
t - 2 = 0
We'll apply quadratic
formula:
t1 = [1 + sqrt(1 +
8)]/2
t1 = (1 + 3)/2
t1 =
2
t2 = -1
log3 x =
t1
log3 x = 2
x =
3^2
x1 = 9
log3 x =
t2
log3 x = -1
x2 =
3^-1
x2 =
1/3
The solutions are: {1/3 ;
9}.
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