例谈角的变换技巧李爱卿在三角函数中，角的变换是一种重要的基本变换。通过观察分析条件和所求（证）角之间的内在关系，使条件和所求（证）角间实现巧妙的转化，从而使问题得到解决。以下仅举几例。此题角的变换技巧是：例２已知：ｓｉｎ（ｘ－α）＝，ｓｉｎ（ｘ＋α）... Example Angular Transformation Techniques Li Aiqing In the trigonometric function, the transformation of the angle is an important basic transformation. By observing the intrinsic relationship between the analysis conditions and the requested (certificate) angle, the ingenious transformation between the condition and the requested (certificate) angle is achieved, so that the problem is solved. Here are just a few examples. The transformation skills of this title angle are: Example 2 is known: sin(x-α)=,sin(x+α)...