Question

как решить? плиз  lg(3x-11)+lg(x-27)=3

Answer 1

lg(3x-11)+lg(x-27)=3                         ОДЗ:   3х-11>0   и х-27>0
lg(3x-11)(x-27)=lg1000                                 3x>11         x>27
(3x-11)(x-27)=1000                                       x>3 2/3
3x²-11x-81x+297-1000=0                             x>27
3x²-92x-703=0
D=(-92)²-4*3(-703)=16900=130²
x1=6 1/3<27           x2=37
Ответ: 37