... ABbACc(4;2),(3;4) =-- =-- uuuruuur. Ta cú: ABACBC2.050ỡù=ớ=ùợuuuruuur bcbc5,01,6ộ==ờ =-= ở ị ABCABC(3;2),(1;5),(0;2)(3;2),(1;1),(6;2) -- -- - . Trn S Tựng 2) u (2;1;1)D=-r. Gi H = d ầ D. Gi s Httt(12;1;) +-+ - ... MHttt(21;2;) =-- -uuuur. MHuD^uuuurr ttt2(21)(2)() 0-+ -- - = t23= ị duMH3(1;4;2)= =-- uuuurr ị d: xtytzt2142ỡ=+ù =- ù=ợ. Cõu VII.b: H PT xyxyxyxy55535log(32)log(32)1log(32)log5.log(32)1ỡ+ +-= ớ +-- =ợ xyxy55log(32)1log(32)0ỡ+= -= ợ ... tttt2121402140 -- -= ớ +-= ợ tt122218ỡ =- =ợ ị AB(52;16;32),(18;16;32 )-- -. ị Phng trỡnh ng thng d: xtyz521632ỡ =-+ ù =- ù=ợ. Cõu VII.a: Phn thc a = 88, phn o b = 59. 2. Theo chng trỡnh nõng cao Cõu VI.b:...