tan10tan20+tan20tan60+tan70tan10=?

来源：学生作业帮编辑：神马作文网作业帮分类：数学作业时间：2024/11/18 05:20:47

tan10tan20+tan20tan60+tan70tan10
= (tan10+tan60)tan20 + tan70tan10
= tan70*(1-tan10tan60)*tan20 + tan70tan10
= tan70 (tan20+tan10- tan10tan20tan60)
= tan70 [tan30(1-tan10tan20)- tan10tan20tan60]
= tan70 tan30 - tan10tan20tan70(tan30+tan60)
= tan70 tan30 - tan10(tan30+tan60)
= tan30(tan70-tan10) - tan10tan60
= tan30tan60*(1+tan70tan10) - tan10tan60
= 1+tan70tan10- tan10tan60
= 1+ tan10(tan70-tan60)

高一数学tan10tan20+tan20tan60+tan60tan10,数字都是度数,求值或化简 = - = 、、、、 ==== =? - = 、、、 &，！！=)*#; ==============？ ============== 英语翻译===================================:211.174.59.110 faile :@+@=&+&+& &+&+&=*+*+*+* @+&+*+*=400 @=?&=?*=? ...............................快一点=================