of Iocutna ngc rY r wnaNmrAuoANQuAN t PHoNG crlo ngc vAoAo r4o I,[AM HQc 2ol9 -2020 s lr0x' rbix-xn6t Ngny ki6m tua: 16 thring ET CHiNH THUC Thdi (g6m 01 trang) giai: 90 12rfim2019 -, phttt 1kh6ng tli thdt gtan phtu da) CdaLt (2,0 ifi6m) ThUc hiQn ph6P tinh, n1t gqn: a)(x-2Xx+3)+(x+ lF + *4*,-30 ("6ix+t3) b) ' x+3 x-3 x'-9 Cdul: (2,0 ildnl Phdn tich c6c da thrlc sau thdnh nh6n tl: a)3* -12y2 b)x2-y2-4x+4 Ci;a3z (1,0 ifrfirn) : Ttm x bi6t 3x(x - 2) - x(3x - t; 16 Cda 4t (1,0 ifrdm) s = 612 DiQn tich hinh cht nhat ABCD (tlnh theo x) dugc cho bdi bi6u thr?c ddi b6ng 3x + hinh v€-duoi d6y Tinh chiAu rgng hlnh ch6 nhflt theo x bi{5t ohiAu E A + 5x - nhu C JXi-+ D (1,0 fr€m) CduS: ctia trlr b{p benh E 50 cm vi Hai bpn Binh rzi An c6ng vi€n choi b$p bcnh Bi6t chi6u cao c6ch m4t ddt' H6i m5i ban c6ch khoang c6ch cria An c6ch -6t aat g6p + fan moang cdch c'baBir:h m4t dAt bao nhi€u cm? A M D Cdu 6r (3,0 ili6m) Cho tam gi6c ABC rmdng t4i 50 rt I) N A (AB < AC), ggi D, E' M Dn luqt li trung di6m cria AB' AC vd BC chtr nhflt' Clllng minh: T{r gi6c CMDE la htnh blnh hatrh vd ADME ld hlnh ld di6m d6i xrmg crta M qua E Chimg b) K6 ducrng cao AH cria tam gi6c ABC G{ ro vd I c6n' minh trl gi6c AICM 1d hinh thoi vi DEMH li hinh thang c) Chring minh: AH2 : BH CI{ a) -utt- gl tk€m) (Thi sinh kbhng dwgc s{r ttrTng tii liQu'Gidm tk! khbng gi&i tkich Hg vi t0n: " SBD: """""""'- Truong:""""""'