论文部分内容阅读
三角恒等证明灵活多变,其方法多种多样。第一种证明方法,由左式化到右式,叫做顺证法。例如,求征:sinα/(1-cosα)=(1+cosα)/sinα由sinα/(1-cosα)=sinα(1+cosα)/(1-cosα)(1+cosα)即可化到右式。第二种证明方法,由右式化到左式,叫做逆证法。如前例,由(1+cosα)/sinα=(1+cosα)(1-cosα)/sinα(1-cosα),即可化到左式。第三种证明方法,由左式、右式同时化简,得出第三量,通过等量代换,证出结论,叫做并证法。
Triangular proof of flexibility, its methods vary. The first method of proof, from left to right type, is called the law of evidence. For example, find: sinα / (1-cosα) = (1 + cosα) / sinα can be derived from sinα / (1-cosα) = sinα (1 + cosα) / (1- cosα) (1 + cosα) Right type. The second method of proof, from right to left type, called the inverse card method. As in the previous example, the formula to the left is given by (1 + cos α) / sin α = (1 + cos α) (1-cos α) / sin α (1-cos α). The third method of proof, by the left-style, right-style at the same time simplify, come to the third volume, through the equivalent substitution, to prove the conclusion, called and evidence method.