1.How to “convexify” a non-convex function?
https://math.stackexchange.com/questions/2872861/how-to-convexify-a-non-convex-function
∇2𝑓(𝑎,𝑚)≤0 is the definition of deciding whether the function is convex or nonconvex
https://math.stackexchange.com/questions/2872861/how-to-convexify-a-non-convex-function
∇2𝑓(𝑎,𝑚)≤0 is the definition of deciding whether the function is convex or nonconvex