Question

Maka nilai x adalah...

#mohondibantuyaaa

Answer 1

Det P = x . x - 2 . 1 = x^2 - 2
det Q = x . 2 - (-3) . 1 = 2x + 3

det P = 3 . det Q
x^2 - 2 = 3(2x + 3)
x^2 - 2 = 6x + 9
x^2 - 6x - 11 = 0
x^2 - 6x = 11
x^2 - 6x + 9 = 11 + 9
(x - 3)^2 = 20
(x - 3) = ± √20
x = 3 ± 2√5
x = (3 + 2√5) atau x = (3 - 2√5)