KTHITHIHCLN1NMHC2013ư2014 TRNGTHPTCHUYấNVNHPHC Mụn:Toỏn12.Khi A,A1,B. chớnhthc (thigm01trang) 1) Khosỏtsbinthiờnvvthcahmskhi m =1 2) Tỡmttccỏcgiỏtrcathams m ạ0 saochotiptuyncathtigiaoimcanúvi trctungtovihaitrctomttamgiỏccúdintớchbng4. Cõu2 (1,25 im) Giiphngtrỡnh: ) ( ) - cos 2x + + sin 2x = ( sin x + cos x ) ( ) sin x + cos x - -3 x ỡ ù x - x = y- y Cõu3.(1,25im) Giihphngtrỡnh: ( x, yẻ Ă). ù 5y -1 - x y = ợ x + - x + Cõu4 (1,0im) Tớnhgiihn: L = lim x đ x -2 Cõu5.(1,0im).Chohỡnhchúp S ABCD cúỏylhỡnhvuụngvicnh 2a ,mtbờn ( SAB) nm trongmtphngvuụnggúcvimtphng ( ABCD) v SA = a ,SB =a Hóytớnh thtớchcahỡnhchúp S ABCD vkhongcỏchgiahaingthng AC v SB theo a Cõu6.(1,0im).Xộtcỏcsthcdng a, b,c thomón ab + bc + ca =7abc Tỡmgiỏtr nh nht cabiuthc: P= THIKHSCLLNINMHC2013 2014 HNGDNCHMTON12A,B,A1 Thigianlmbi:180phỳt(Khụngkthigiangiao) A.PHNCHUNGCHOTTCTHSINH(8,0im) Cõu 1.(2,5im).Chohms y = mx - ( 2m + )x + m +1 ( Cm ) ( SGDưTVNHPHC TRNGTHPTCHUYấN 8a + 108b5 + 16c6 + + + a2 b2 c Hngdnchung. Mimtbitoỏncúthcúnhiucỏchgii,trongHDCnychtrỡnhbyslcmtcỏch gii.Hcsinhcúthgiitheonhiucỏchkhỏcnhau,nuývchoktquỳng,giỏmkho vnchoimtiacaphnú. Cõu(Hỡnhhckhụnggian),nuhcsinhvhỡnhsaihockhụngvhỡnhchớnhcabitoỏn, thỡkhụngchoimcõu(Hỡnhhcgiitớch)khụngnhtthitphivhỡnh. imtonbichmchititn0.25,khụnglmtrũn. HDCnycú04 trang. Cõu Nidungtrỡnhby im 1. Khi m = 1: y = x 3- x +2 +TX: Ă 0.25 +Sbinthiờn: y  = x - = ( x - 1)( x + 1), y  = x = y  > x < -1 x >1 suyrahmsngbintrờn cỏckhong ( -Ơ -1) , (1 +Ơ) y  < -1 < x