三角函数最值问题是三角函数性质的重要组成部分,解决这类问题的基本途径,同求解其他函数最值一样,一方面应充分利用三角函数自身的特殊性(如单调性,有界性),另一方面还要注意三角函数最值问题转化为求一些我们所熟知的函数的最值问题。一、利用三角函数的有界性在三角函数中,正弦函数与余弦函数具有一个最基本也是最重要的特征——有界性。利用正弦函数与余弦函数 The trigonometric function is an important part of the trigonometric function. The basic way to solve such problems is the same as solving the other functions. On the one hand, we should make full use of the particularity of the trigonometric function (such as monotonicity and boundedness). On the other hand, we must also pay attention to the problem of converting the trigonometric function to the value of some function that we know well. First, the use of the boundedness of the trigonometric function In the trigonometric function, the sine function and the cosine function have one of the most basic and most important features - boundedness. Using sine and cosine functions