数学附录 12拟凸函数: A function f defined on a convex set XcRn is said to be quasi-- convX, if for any xand x” in X and anyλ∈[0,1: f(1-)x,+x”)≤min{f(x),f(x”)} f is said to be strictly quasi- convex, if the sign“≤” in the a bove inequality is replaced with“<” Any convex(strictly convex) function is quasi-convex(strictly quasi-convex), but the converse is not true.数学附录 • 12 拟凸函数：A function f defined on a convex set Xn is said to be quasi-convx, if for any x’ and x” in X and any [0, 1]: f((1-)x’+x”)  min {f(x’),f(x”)} • f is said to be strictly quasi-convex, if the sign “ ” in the above inequality is replaced with “<”. . Any convex (strictly convex) function is quasi-convex (strictly quasi-convex),but the converse is not true