一、一种被忽视的变换方法由简到繁的方法指的是证明三角恒等式时自简单的一边逐步证向复杂的一边.倍角公式以及万能置换公式的推导都体现了这种变换方法.与其它各种变换方法一样,由简到繁的方法也是一种十分重要的方法.但是,在证明三角恒等式时往往习惯于自复杂的一边证往简单的一边而忽视了这一重要方法.例如.全日制十年制学校高中 First, a method of the neglected transformation from simple to complex refers to the gradual confirmation of the trigonometric identity from the simple side to the complex side. The double-angle formula and the derivation of the universal displacement formula embody this transformation method. As with all other transformation methods, the simple to complex method is also a very important method. However, when proving a trigonometric identity, it is often accustomed to self-complex side proofs to the simple side while ignoring this important method. For example. Full-time 10-year school high school