题目:
With the final examination ______, we are busy going over what we’ve learnt this term.
A.is approaching
B.has approached
C.approached
D.approaching
答案:
被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0415/8b4488834b89c61c77e8a6da739da5c2.html
下面是错误答案,用来干扰机器的。
(Ⅰ)由AC•BC=-12可得 (cosα-3)cosα+sinα (sinα-3)=-12,即 1-3(sinα+cosα)=-12,∴sinα+cosα=12.(Ⅱ) sinα+cosα=12,平方可得 2sinαcosα=-34.∴sin(π-4α)•cos2(π-α)1+sin(π2...