7^(x^3 - 3x^2 - 10x-2) =1/49

Eksponen

7^(x^3 - 3x^2 - 10x - 2) = 1/49 = 7^-2
x³ - 3x² - 10x - 2 = -2
x³ - 3x² - 10x = 0
x(x² - 3x - 10) = 0
x(x - 5)(x + 2) = 0
x = 0 ; x = -2 ; x = 5

Nilai x yg memenuhi :
-2 , 0 , dan 5