Question

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

Answer 1

1/lgx+4lgx^2+9=0
1/lgx+8lgx+9=0
x>0 x≠1
1+9lgx+8lg^2x=0
lgx=-1  lgx=-1/8
x1=0,1
x2=1/10^(1/8)