Let $(x) = ax^2 + bx + 18 be a quadratic polynomial. If the minimum value of f(x) = 6 when x = \(4\), find a + b.

Guest Feb 1, 2022

#1**+1 **

We know the minimum of this bowl shaped ( if a is positive value) parabola will occur at x = - b/2a

so 4 = - b/2a

and the value at x = 4 is 6

16 a + 4b + 18 = 6 Now you have two equations and two unknowns.....can you solve for a and b from here ?

ElectricPavlov Feb 1, 2022