7 (√2) pangkat x -2 pangkat x=-8

Eksponen

7 (√2)^x - 2^x = -8

Misal :
2^(x/2) = a

7a - a² = -8
a² - 7a - 8 = 0
(a - 8)(a + 1) = 0
a = 8 atau a = -1

Yg memenuhi : a = 8
2^(x/2) = 8
2^(x/2) = 2^3
x/2 = 3
x = 6 ✔