Question

Persamaan mempunyai akar kembar, maka nilai m adalah..

Answer 1

akar kembar atau hanya memiliki satu penyelesaian , ingat :
D = 0
b² - 4ac = 0
(8-2m)² - 4(1-m)(12) = 0
64 -32m + 4m² -48 + 48m = 0
4m² + 16m + 16 = 0
(m + 2)(4m + 8) = 0
m = -2

Answer 2

Akar kembar --> D = 0
D = b^2 - 4.a.c =0
(8 - 2m)^2 - 4(1 - m)(12) = 0
64 - 32m + 4m^2 - 48 + 48m = 0
4m^2 + 16 + 16m = 0 --> dibagi 4
m^2  4m + 4 = 0
(m + 2).(m + 2) = 0
m = -2