Question

(log2 x)^-1 +4log2 x^2 +9=0

Answer 1

log2 x=t

1/t+8t+9=0

1+8t^2+9t=0

[-9+-sqrt(81-32)]/16=[-9+-7]/16

t1=-1

t2=-1/8

log2 x=-1  x=1/2

log2 x=-1/8 x=-3