1) 1 inf cosA+cosB+cosC inf 3/2
2) 1 inf sin(A/2)+sin(B/2)+sin(C/2) inf 3/2
3) sinA+sinB+sinC inf 3/2rac3
4) cosA/2+cosB/2+cosC/2 inf 3/2rac3
5)cotA+cotB+cotC sup rac3
6)tanA/2+tanB/2+tanC/2 sup rac3
7)cotA/2+cotB/2+cotC/2 sup 3rac3
8)dans un triangle acutangle tanA+tanB+tanC sup 3rac3
9)sinA/2.sinB/2.sinC/2 inf 1/8
10)cosA.cosB.cosC inf 1/8
11)sinAsinBsinC inf 3rac3/8
12)cosA/2cosB/2cosC/2 inf 3rac3/8
13)cos²A+cos²B+cos²C sup 3/4
tu be continued...