思维品质是指个体思维活动特殊性的外部表现.它包括思维的严密性、灵活性、深刻性、批判性和抽象性等品质.函数作为高中数学的主线,贯穿于整个高中数学的始终.函数的定义域是构成函数的重要因素之一,函数的定义域似乎是非常简单的,然而在解决问题中稍不加以注意,常常会使人误入 Thinking quality refers to the external performance of the particularity of individual thinking activities. It includes the rigor, flexibility, profoundness, criticality, and abstractness of thinking. Functions, as the main line of high school mathematics, run through the entire high school mathematics. The definition of the domain is one of the important factors that make up the function. The domain of the function seems to be very simple. However, paying little attention to the problem often leads to mistakes.