( 5 ^ X ) - 6 * ( 5 ^ - X ) = 3,8 ;
5 ^ X = A ; A > 0 ;
A - ( 6 / A ) = 19/5 ;
A не равен нулю ;
5A^2 - 30 = 19A ;
5A^2 - 19A - 30 = 0 ;
D = 361 + 600 = 961 ;
V D = 31 ;
A1 = ( 19 + 31 ) : 10 = 5 ;
A2 = ( 19 - 31 ) : 10 = - 1,2 ( < 0 ) ;
5 ^ X = 5 ; X = 1
Ответ Х = 1