Bila fungsi y = 2x² + 6x – m mempunyai nilai minimum 3 maka tentukan m. Mohon bantuannya :)

Y = 2x^2+6x-m
a = 2
b = 6
c = -m

y min = (b^2-4ac)/(-4a)
3 = (6^2-4.2.(-m))/(-4.2)
3 = (36+8m)/(-8)
3.(-8) = 36+8m
-24 = 36+8m
-24-36 = 8m
-60 = 8m
m = -60:8
m = -7,5