Tolong dijawab dengan menggunakan jalan/cara

(x^2 - 2ax + a^2) / (x + 1)(x - 4) < 0
(x - a)(x - a) / (x + 1)(x - 4) < 0
x = a atau x = -1 atau x = 4
ada beberapa kemungkinan garis bilangan :
1) +++ (a) +++ (-1) --- (4) +++
HP = -1 < x < 4
=> S = 0 + 1 + 2 + 3 = 6 untuk a < -1

2) +++ (-1) --- (a) --- (4) +++
HP = -1 < x < a atau a < x < 4
jika a = -1 => S = 0 + 1 + 2 + 3 = 6
jika a = 0 => S = 1 + 2 + 3 = 6
jika a = 1 => S = 0 + 2 + 3 = 5
jika a = 2 => S = 0 + 1 + 3 = 4
jika a = 3 => S = 0 + 1 + 2 = 3 ======> nilai S minimum
jika a = 4 => S = 0 + 1 + 2 + 3 = 6

3) +++ (-1) --- (4) +++ (a) +++
HP = -1 < x < 4
S = 0 + 1 + 2 + 3 = 6 untuk a > 4

jadi agar S minimum maka nilai a = 3