如果tan(45+α)=2010,那么1/cos2α+tan2α=
问题描述:
如果tan(45+α)=2010,那么1/cos2α+tan2α=
答
tan(45+α)=2010=(tan45°+tanα)/(1-tan45°*tan²α)=(1+tanα)/(1-tanα)解得tanα=2009/2011cos2α=(cos²α-sin²α)/(cos²α+sin²α)=(1-tan²α)/(1+tan²α)=(1- 2009²...