<span>4^x + 12^x = 2*36^x /:36^x
4^x/36^x + 12^x/36^x = 2
(4/36)^x + (12/36)^x - 2 = 0
(1/9)^x + (1/3)^x - 2 = 0
Пусть (1/3)^x = t
t^2 + t - 2 = 0
D = 1 + 8 = 9
t1 = ( - 1 + 3)/2 = 1
t2 = ( - 1 - 3)/2 = - 2
Обратная замена
(1/3)^x = 1
x = 0
(1/3)^x = - 2
Нет решений
Ответ
0</span>
Считаю что предел стремится к бесконечности(условие у Вас неполное)
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