There are several expressions for quadratic inclusions

There are several expressions for quadratic inclusions

In general, there is the following relationship between the independent variable x and the dependent variable y: y = ax ^ 2 + BX + C (a ≠ 0, a, B, C are constants), then y is called the quadratic function of X. important concepts: (a, B, C are constants, a ≠ 0, and a determines the opening direction of the function. When a > 0, the opening direction is upward, a ≠ 0