论文部分内容阅读
在三角函数的化简和求值中,常常遇到由sinx±cosx的值确定角x的范围,以及由角x确定sinx±cosx值的正负,在解这类问题时学生经常出错。在三角函数的复习教学中,如果通过单位圆归纳总结,学生掌握起来就比较容易了,现介绍于后。 由单位圆不难得到下面结论,这些结论可由下图形象地记忆(文中出现的k∈Z)。
In the simplification and evaluation of trigonometric functions, it is often encountered that the range of angles x is determined by the value of sinx ± cosx, and the positive and negative values of sinx ± cosx are determined by angle x, and students often make mistakes in solving such problems. In the review of trigonometry function teaching, if summarized by the unit circle summary, students grasp it easier, are introduced in the later. From the unit circle is not difficult to get the following conclusions, these conclusions can be vividly memory (the text appears k∈Z).