函数的周期性是函数的一个重要性质.在苏教版的教材中关于周期性研究最多的是三角函数,而对非三角函数的周期性未加提及,因此不少学生错误地认为只有三角函数才有周期性,非三角函数没有周期性.其实不然,因为一些非三角函数如果既有点对称又有轴对称,也可使得这类函数具有周期性.纵观近年的各类考试题,关于函数周期性的考 The periodicity of the function is an important property of the function. In the textbook of the Jiangsu Education Press, the most frequently studied is the trigonometric function, while the periodicity of the non-trigonometric function is not mentioned, so many students mistakenly believe that only the triangle The function has periodicity, non-trigonometric functions have no periodicity. This is not true, because some non-trigonometric functions can be periodic if they are both symmetrical and axisymmetric. Looking at various examination questions in recent years, about Periodic test of function