(1+lgx)^2-lgx-3>=0
1+lg^2x+lgx-3>=0
lg^2x+lgx-2>=0
x>0
lgx>=1 x>=10
lgx<=-2 x<=0,01
0<x<=0,01 U x>=10
lg^210x-lg^x≥lg1000
210х-х≥1000
209х≥1000
х≥1000/209
