Question

Inii gimanna lahh tinggal 2 soal lagii mohon dibantu lahh pliszzzz

Answer 1

A) 3^(2x + 2) + 8.3^x - 1 = 0
misal:
3^x = a , maka:
9a² + 8a - 1 = 0
(9a - 1)(a + 1) = 0
9a = 1          a = - 1 (tidak memenuhi)
a = 1/9
3^x = 3^-2
x = - 2

b) 5^(2x - 1) - 6.5^x + 25 = 0
misal: 5^x = p , maka:
p²/5 - 6p + 25 = 0
p² - 30p + 125 = 0
(p - 5)(p - 25) = 0
p = 5 --> 5^x = 5 maka x = 1
p = 25 --> 5^x = 5^2 maka x = 2