- 8 Tháng ba 2017
- 108
- 30
- 66
- Bình Định
- THPT Chuyên Chu Văn An
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
1/ [tex]S=tan^{2}5^{o}+tan^{2}10^{o}+tan^{2}15^{o}+...+tan^{2}85^{o}[/tex]
2/ [tex]A=sin2^{o}.sin18^{o}.sin22^{o}.sin38^{o}.sin42^{o}.sin58^{o}.sin62^{o}.sin78^{o}.sin82^{o}[/tex]
2/ [tex]A=sin2^{o}.sin18^{o}.sin22^{o}.sin38^{o}.sin42^{o}.sin58^{o}.sin62^{o}.sin78^{o}.sin82^{o}[/tex]