Question

Помогите решить, хд.
Показательные уравнения ​

Answer 1

1. 5^(x - 2) = 25

5^(x-2) = 5^2

x-2 = 2

x=4

2. 3^(x-4)=1

3^(x-4)=3^0

x-4=0

x=4

3. 2^(x+2) + 2^x = 5

2^x(2^2 + 1) = 5

2^x = 1

x = 0

4. 9^x - 6*3^x - 27 = 0

3^x = t > 0

t^2 - 6t - 27 = 0

D = 36 + 4*27 = 144 = 12^2

t12 = (6 +- 12)/2 = -3  9

t=-3 Нет

t = 9

3^x = 9

x = 2