wWw.VipLam.Info KHO ST LP 12 MễN TON KHI A NM HC 2010-2011 Thi gian 180 phỳt (Khụng k thi gian giao ) I/.PHN CHUNG CHO TT C TH SINH(7,0 im) x + 4mx + 4m ,(1) 1) Kho sỏt s bin thiờn v v th (C ) ca hm s (1) m = 2) Tỡm giỏ tr ca m hm s (1) cú cc tr, ng thi ba im cc tr ca th xỏc nh mt tam giỏc cú bỏn kớnh ng trũn ngoi tip bng Cõu I (2 im): Cho hm s y = Cõu II(2 im): 1)Gii phng trỡnh sau: ữsin x ữ = 4sin x sin x 2sin x 3 y (3 x 1) = 125 2)Gii h phng trỡnh sau: 2 45 x y + 75 x = y x + ( x + sin x)sin x dx (1 + sin x )sin x Cõu IV(1 im): Cho hỡnh chúp S.ABCD cú ỏy ABCD l hỡnh bỡnh hnh cú cnh AB=a,cnh AD=b,gúc ã BAD = 60 CnhSA=4a v SA vuụng gúc vi mt phng (ABCD).Trờn on SA ly im M cho AM=x (0 ... 45 x y + 75 x = y Chia c hai v pt(1) v pt(2) ln lt cho y 0; y ta cú h pt 0,25 wWw.VipLam.Info 125 125 3 27 x + =9 27 x + = 3 y y u = x ; v = , v Ta cú (*) t y 5 x x 45 + 75 = x x... 3t ) + ( t 3) = 20 10t + 10 = 20 t = t=1.Suy A(6;1) C(-2;5) v B(0;-1) D(4 ;7) TH2:(AB) 3x-y +7= 0 Gi A(t;3t +7) vỡ A cú honh x A > nờn t>0 v IA2 = 2.R = 20 t = 2 nờn ( t ) + ( 3t + ) = 20... cú (*) t y 5 x x 45 + 75 = x x + ữ= y y y y u + v = (u + v )3 3uv(u + v) = (u + v )3 = 27 u + v = (*) tr thnh uv = uv(u + v) = uv (u + v) = uv(u + v) = u = u = Suy : hoc v = v =