Question

Bantu jawab nomor 24

Answer 1

H(t) = 5 + 20t - (5/4)t^2
h'(t) = 20 - (5/2)t = 0
=> -(5/2)t = -20 => t = 20 . 2/5 = 8
h(8) = 5 + 20(8) - (5/4)(8)^2 = 5 + 160 - 80 = 85

Dengan rumus fungsi kuadrat juga bisa
y = D/(-4a) = (b^2 - 4ac)/(-4a)
= (20^2 - 4(-5/4)(5)) / (-4(-5/4))
= (400 + 25)/5
= 425/5 = 85