Question

log3(14-x)=2log3 5                          Решите пож-ста.

Answer 1

ОДЗ   14-x > 0 ; x < 14
log3(14-x)=2log3 5    
log3(14-x)=log3 5^2    
14-x = 5^2
14-x =25
x = 14-25 = -11
x = -11