... bin c ó cho, suy A = C20 C16C4 Vy xỏc sut ca bin c A l P ( A) = 5 A C20 C16C4 16 80 = = 10 C40 12 617 Tớnh din tớch, tỡm ta im .www.mathvn.com m AB = (2;2 ;1) , AC = (1; 3 ;1) [ AB, AC ] = (5;3;4) ... TRNG THPT ễNG SN I Kè THI KSCL TRC TUYN SINH NM 2 015 ( LN 1) P N THANG IM MễN TON im Cõu Ni dung 1a Kho sỏt hm s v v th hm s 2,00 Khi m = 1, ta cú hm s y = x + 3x 1) Tp xỏc nh : D ... x 11 1x + 327 x 225 = x = 1, x = 3, x = Do x 0,5 25 nờn x = x = 1, x = (loi) f (3) = 6, f (1) = 10 , f (0) = suy max f ( x) = f (1) = 10 [ 3; ] 0,25 Nh vy 2( x + y + z ) xyz f ( x) 10 ...