> 数学 >
已知:tana-1/tana=-1,求1/[sina^2+2sina·cosa-(cos^2)·a]得值
人气:168 ℃ 时间:2020-02-04 01:31:08
解答
sina/cosa-cosa/sina=-1(sin^2a-cos^2a)/sinacosa=-1sin^2a-cos^2a=-sinacosa1/[sina^2+2sina·cosa-(cos^2)·a]=1/sinacosa=sin^2a+cos^2a/sinacosa=sina/cosa+cosa/sina=tana+1/tanatana-1/tana=-1tan^2a+1/tan^2a...
推荐
猜你喜欢
© 2024 79432.Com All Rights Reserved.
电脑版|手机版