+23254 This is the equation of a parabola. Since this parabola opens upward, the vertex will be the lowest point. The x-value of the vertex is found by -b/(2a).
a = 2 b = -8 ---> -(-8)/(2·2) = 8/4 = 2
f(4) = 2(2)² - 8(2) + 19 = 11 <--- The minimum value of the function.
