... 1, , 2 2 2 2,d K SAHSK a d K SAH d B SAH BISBd B SAH ị = = ị = = =0 ,25 Doa,b,c>0v 2 2 2 1a b c + + = nờn ( ), , 0 1a b c ẻTacú ( ) 2 25 31 2 3 2 2 2 1 a a a a a a a b c a - - + ... 90 ,25 III(1im) = + = 2 1 I 3 I I 3 e 2 2 2 5 3 + - 0 ,25 IV(1im)*Tacú2IA IH = - ị uur uuurHthuctiaicatiaIAv 2IA IH = 2 2BC AB a = =Suyra3, 2 2 a aIA a IH AH IA IH = = ị = + =0 ,25 SHC A BIK.SGD&TTHANHH A TRNGTHPTBMSNKTHITHIHCLN2NM2011HNGDNCHMMễN:TONKHI :A (Thigianlmbi180khụngkthigianphỏt)Cõu ... Tacú5 2 2 2 0 2 . .cos 45 2 a HC AC AH AC AH HC = + - ị =Vỡ ( ) ( ) ( )150 0, 60 .tan 60 2 a SH ABC SC ABC SCH SH HC ^ ị = é = ị = =0 ,25 Tacú5 2 2 2 0 2 . .cos 45 2 a HC AC AH AC AH...