I want the detailed knowledge of quadratic function, and then add exercises with answers (otherwise I don't know right or wrong)~

I want the detailed knowledge of quadratic function, and then add exercises with answers (otherwise I don't know right or wrong)~

A quadratic function is a polynomial function of which the highest degree of the unknown is quadratic. A quadratic function can be expressed as f (x) = ax ^ 2 + BX + C (a is not 0). Its image is a parabola whose principal axis is parallel to the Y axis. Generally, there is the following relationship between the independent variable x and the dependent variable y: general formula: 1: y = ax