X=/=1
x>0
Преобразовывая по формуле log(a)b=1/log(b)a
log(x)(2x^-1)*log(x)(2x^2)*log(x)(2x)*log(x)(2x^-2)<40 <br>
(log(x)2-1)(log(x)2+2)(log(x)2+1)(log(x)2-2)<40 <br>
log(x)2=t
(t^2-1)(t^2-4)<40 <br>t^4-5t-36<0 <br> D=13^2
t=9,-4
x E (0, 1/2^(1/3)) U (2^(1/3), +oo)