ĐỀ THI THỬ THPT MÔN TOÁN LỚP 10 TRƯỜNG CHUYÊN

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AD = AH . BD =fH@: ã 0 ACB 90 (góc nội tiếp chắn nửa đ ờng tròn)= 2 BH . BA = BC %4'e1'"7C9'/ .1@: BH BC BHC BFD (g-g) BH . BD = BC . BF BF BD = ~ ã ã DCB BCE = ã ả 2 2 D E =  BH.(BA+BD) = BC.(BC + BF) BH . AD = BC . CF (1)⇒ ⇔ haF@:iiOS%j'/@'Nk  ¶ · · · 2 0 D CAB (so le trong) AH AC ACH DF BD mµ AHC DFB 90  ⇒ =  ⇒ ∆ ∆ ⇒ =   = =  ~ DBF (g- g) AH . BD = DF . AC (2)⇒ haF: AC CF ABC CDF (g -g) BC . CF = DF . AC (3) BC DF ∆ ∆ ⇒ = ⇒ ~ l%I%'%#9:HR<OR<HO $*9@:     + + + = + + +  ÷  ÷     1 1 21 3 21. 3. 21 3a b a b b a b a )N > , 0a b <m2(n>"o/#?"7p: + ≥ × = 3 3 21 2 21 6 7a a a a % + ≥ × = 21 21 3 2 3 6 7b b b b % _l'MA%'%"7p:     × + + × + ≥  ÷  ÷     1 1 21 3 12 7a b a b h: = = 12 7 144.7 1008 I = = 2 31 31 961 ⇒ > 12 7 31 ⇒     × + + × +  ÷  ÷     1 1 21 3 > 31a b a b %"2  . 2m m + 2 2 2 2 2 (4 2) 2.(4 2) .100 6 100 6 100 6 2m m + + 2 2 2 2 (4 2) 100 6 (100 6 2) - (100 6 2)m ="19,->F = = = 2 2 2 4 2 100 6 0 4 100 8 252m m m = = 6 7 6 7 m m -"eF42789!@4 P"@=W% T * +. =  +  2 2 2 2 10 5 1 1 (I) 20 3 11 1 y x y y x y `a = 2 x u % ≥ 0u ' = + 2 10 1 y v y R4%b9c: − = − = = =     ⇔ ⇔ ⇔     + = + = − = =     5 1 10 2 2 13 13. 11 5 1 4 u v u v u u u v u v u v v  )N = = = 2 1 1 1u x x )N = = = + = + = 2 2 2 10 4 4 4 10 4 0 1 1 2 y y v y y y y B.1>4%b"'N = = = 1 1; 2 hoặc 2 x y y <)^4%b@4%II%I 1 2 I%WII%WI 1 2 #*/1234.563/* +