求证tan(x-y)+tan(y-z)+tan(z-x)=tan(x-y)tan(y-z)tan(z-x)tan(x-y)+tan(y-z)怎么化成tan〔(x-y)+(y-z)〕?

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/19 08:23:52
求证tan(x-y)+tan(y-z)+tan(z-x)=tan(x-y)tan(y-z)tan(z-x)tan(x-y)+tan(y-z)怎么化成tan〔(x-y)+(y-z)〕?
x){ƒ< JMmR ¨ҭдId`Z5=gڳ @ SxSqT{"}&b;K^,tRϳv?m]tO=`މ kaU~.bDmnPuĩх1BK=P>lx{) 竻fɎgM8}qAb( ?0

求证tan(x-y)+tan(y-z)+tan(z-x)=tan(x-y)tan(y-z)tan(z-x)tan(x-y)+tan(y-z)怎么化成tan〔(x-y)+(y-z)〕?
求证tan(x-y)+tan(y-z)+tan(z-x)=tan(x-y)tan(y-z)tan(z-x)
tan(x-y)+tan(y-z)怎么化成tan〔(x-y)+(y-z)〕?

求证tan(x-y)+tan(y-z)+tan(z-x)=tan(x-y)tan(y-z)tan(z-x)tan(x-y)+tan(y-z)怎么化成tan〔(x-y)+(y-z)〕?
两角和正切公式:
tan[(x-y)+(y-z)]=[tan(x-y)+tan(y-z)]/[1-tan(x-y)tan(y-z)]
tan(x-y)+tan(y-z)
=tan(x-y+y-z)*[1-tan(x-y)tan(y-z)]
=tan(x-z)*[1-tan(x-y)tan(y-z)]
=tan(x-z)-tan(x-z)tan(x-y)tan(y-z)
=-tan(z-x)+tan(z-x)tan(x-y)tan(y-z)
所以tan(x-y)+tan(y-z)+tan(z-x)=tan(x-y)tan(y-z)tan(z-x)成立
写得很清楚的,你难道还看不懂么?