4) log^2x_3 - log_3 x - 6= 0
log_3x = z
z^2 -z - 6 = 0
z1 = -2
z2 = 3
a) log_3 x = - 2
x = 3^(-2)
x1 = 1/9
b) log_3 x = 3
x = 3^3
x2 = 27
2) log_6 x + log_6 y = 2
x - y = - 5
ОДЗ: x > 0, y > 0
x = y - 5
log_6(y - 5) + log_6 y = 2
log_6 y*(y - 5) = 2
y*(y - 5) = 6^2
y^2 - 5y - 36 = 0
y1 = 9
y2 = - 4 не удовлетворяет ОДЗ
x1 = 9 - 5
x1 = 4
Ответ: (4;9)