We'll write log2 (4) = log2
(2^2)
We'll apply the power
property:
log2 (2^2) = 2*log2
(2)
But log2 (2) = 1 => log2 (4) =
2
We'll write log(x) 8 = 1/log (8)
x
log(2) x =log(8) x*log(2)
8
log(2) 8= log(2) (2^3)
We'll
use the power property of logarithms:
log(2) (2^3) =
3log(2) (2) = 3
log(2) x =3*log(8) x => log(8)
x=log(2) x/3
The equation will
become:
log(2) x - 2 - 3/log(2) x =
0
[log(2) x]^2 - 2log(2) x - 3 =
0
Let log(2) x be t:
t^2 - 2t
- 3 = 0
t1 = [2+sqrt(4 +
12)]/2
t1 = (2+4)/2
t1 =
3
t2 = -1
log(2) x = 3
=> x = 2^3 => x = 8
log(2) x = -1 => x
= 2^-1 => x = 1/2
The requested
solutions of the equation are: x = 1/2 and x = 8.
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