Characteristic function is aimed at abstract function. This is a special example of a concrete function. In other words, some concrete functions abstract the same features and get abstract functions.

You're talking about specific functions. The law of its value function is very clear.

A=2m，B = 1–m，C =– 1–m，

m & gt0，a = 2m & gt0

M<0, a = 2m<0, when m is less than 0, the opening is downward. Y decreases with the increase of x; Symmetry axis is

-b/2a = m- 1/4m = 1/4- 1/4m