This is a logarithmic
equation.
We'll take logarithms both side of the equation
and the logarithms will have the base 2:
log 2 [x^(1+log 2
sqrtx)] = log 2 16
We'll use the power property of
logarithms and we'll write 16 = 2^4:
(1+log 2 sqrtx) * log
2 x= log 2 2^4
[1+log 2 (x)^1/2] * log 2 x= 4*log 2
2
{1 + [log 2 (x)]/2}* log 2 x=
4
We'll remove the brackets form the left
side:
log 2 x + [(log 2 x)^2]/2 - 4 =
0
2*log 2 x + (log 2 x)^2 - 4 =
0
We'll substitute log 2 x =
t
t^2 + 2t - 4 = 0
We'll apply
the quadratic formula:
t1 =
[-2+sqrt(4+16)]/2
t1 =
(-2+2sqrt5)/2
t1 = -1+sqrt5
t2
= -1-sqrt5
log 2 x =
t1
x1 =
2^-1+sqrt5
x2 =
2^-(1+sqrt5)
x2 =
1/2^(1+sqrt5)
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