在求解有关三角形的问题时,常常需要用到正弦定理、余弦定理及三角形的内角和定理等知识,将已知条件中的边的关系转化为角的三角函数关系式,或将角的三角函数关系转化为边的关系式,从而顺利获解。下面举例说明较为常用的几种转化思路及解题技巧。一、将角的正(余)弦关系式转化为边的关系式在求解有关边的三角形问题时,常常需要运用正(余)弦定理,将已知条件中的角的三角函数关系 In solving the triangle problem, often need to use the sine, cosine and triangle interior angles and theorems and other knowledge, the known conditions of the relationship between the edge into a trigonometric function of the angle, or the angle of the trigonometric function Relationship into the side of the relationship, which successfully resolved. Here are some examples of the more common conversion ideas and problem solving skills. First, the angle of the (Re) string relationship into the relationship between the sides In solving the triangular problem of the edge, often need to use the (string) theorem, known conditions of the trigonometric function of the angle