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函数的单调性与最值

> 定义在R上的函数f（x）对任意两个不相等实数a，b，总有 f(a)-f(b) a-b ＞0成立，则必有（　　） A．函数f（x）是先增加后减少 B．函数f（x）是先减少后增加 C．f（x）在R上是增函数 D．f（x）在R上是减函数

问题：

发布时间：2024-09-12

定义在R上的函数f（x）对任意两个不相等实数a，b，总有

f(a)-f(b)

a-b

＞0成立，则必有（　　）

A．函数f（x）是先增加后减少 B．函数f（x）是先减少后增加

C．f（x）在R上是增函数 D．f（x）在R上是减函数

参考答案：

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定义在R上的函数f（x）对任意两个不相等实数a，b，总有 f(a)-f(b) a-b ＞0成立，则必有（ ） A．函数f（x）是先增加后减少 B．函数f（x）是先减少后增加 C．f（x）在R上是增函数 D．f（x）在R上是减函数

可能感兴趣的题目：

定义在R上的函数f（x）对任意两个不相等实数a，b，总有

f(a)-f(b)

a-b

＞0成立，则必有（　　）

A．函数f（x）是先增加后减少 B．函数f（x）是先减少后增加

C．f（x）在R上是增函数 D．f（x）在R上是减函数