2, SAU KHI NHAN LEN TA DUOC PHUONG TRINH :
ysinx +ycosx -2y = Ksinx +2
\Leftrightarrow (y- k)sinx + ycosx = 2(Y+1)
ban chi can ap dung bat dang thuc bunhiacopsky nhu sau:
((y- k)sinx + ycosx)^2 \leq ( (y-k)^2 + y^2).(sin^2[X] + cos^2[X])
= 2y^2 --2ky +k^2
SUY RA ( 2(Y+1))^2 \leq 2y^2 --2ky +k^2
SAU DO SUY RA DUOC MAX CUA PHUONG TRINH VA BAN EP NO PHAI NHO HON 2/3 LA RA THOI MA !
![Wink ;) ;)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
HOAC BAN CUNG CO THE AP DUNG DK CO NGHIEM CUA PHUONG TRINH :
a^2 +b^2 \geq C^2 THI CUNG RA KET QUA NHU TREN ............CHUC BAN HOC TOT NHA!.. NHA!.......... NHA!
![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
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![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
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