Edited by phuonganh_lms, 25-07-2011 - 09:36.
Hỏi một bài BDT
Started By realmou, 24-07-2011 - 23:09
#1
Posted 24-07-2011 - 23:09
realmou
-
- Thành viên
-
- 2 posts
Lính mới
Cho tam giác ABC,CMR $\sin A+\ sin B+\sin C<1+\sin A.\sin B+\sin B.\sin C+\sin A.\sin C$
#2
Posted 26-07-2011 - 09:42
NguyThang khtn
-
- Hiệp sỹ
-
- 1468 posts
Thượng úy
$\begin{cases}(1-\sin A)(1-\sin B)(1-\sin C) \ge0 \\ \sin A\sin B\sin C \ge0 \end{cases} \Rightarrow DPCM$Cho tam giác ABC,CMR $\sin A+\ sin B+\sin C<1+\sin A.\sin B+\sin B.\sin C+\sin A.\sin C$
Nguồn: Mathscope
It is difficult to say what is impossible, for the dream of yesterday is the hope of today and the reality of tomorrow
1 user(s) are reading this topic
0 members, 1 guests, 0 anonymous users
