Question

Решите неравенство lg(x-8)+lg(x-3)>lg(27-3x)

Answer 1

(х-8)(х-3)>(27-3x)
x²-3x-8x+24-27+3x>0
x²-8x-3>0
x²-8x-3=0
x1=(4+√19)/2≈(4+4,36)/2=8,36/2=4,18
х2=(4-√19)/2≈(4-4,36)/2=-0,36/2=-0,18

-----( - )------- -0,18----(+)----------  4,18----(-)-------- 
 отВЕТ:    Х∈(-0,18;4,18)