{"segment":[{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":10,"ques":" Cho 3 ph\u00e2n s\u1ed1 $\\dfrac{-5^2 - 5 . 3^2}{5^3 + 5^2 . 3^2}; \\dfrac{4^6 . 9^5 + 6^9 . 120}{8^4 . 3^{12} - 6^{11}}; \\dfrac{2929 - 101}{2 . 1919 + 404}$ <br\/> Sau khi r\u00fat g\u1ecdn v\u00e0 quy \u0111\u1ed3ng ta \u0111\u01b0\u1ee3c 3 ph\u00e2n s\u1ed1 n\u00e0o?","select":["A. $\\dfrac{-1}{15}; \\dfrac{4}{15}; \\dfrac{2}{15}$","B. $\\dfrac{-1}{15}; \\dfrac{12}{15}; \\dfrac{10}{15}$","C. $\\dfrac{-3}{15}; \\dfrac{12}{15}; \\dfrac{10}{15}$","D. $\\dfrac{-1}{15}; \\dfrac{4}{15}; \\dfrac{10}{15}$ "],"hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> R\u00fat g\u1ecdn c\u00e1c ph\u00e2n s\u1ed1 tr\u00ean <br\/> V\u1edbi ph\u00e2n s\u1ed1: $\\dfrac{4^6 . 9^5 + 6^9 . 120}{8^4 . 3^{12} - 6^{11}}$ \u0111\u01b0a c\u00e1c th\u1eeba s\u1ed1 v\u1ec1 c\u01a1 s\u1ed1 2 v\u00e0 c\u01a1 s\u1ed1 3 r\u1ed3i r\u00fat g\u1ecdn <br\/> V\u1edbi ph\u00e2n s\u1ed1 $\\dfrac{2929 - 101}{2 . 1919 + 404}$ nh\u00f3m 101 ra ngo\u00e0i r\u1ed3i r\u00fat g\u1ecdn <br\/> <b> B\u01b0\u1edbc 2: <\/b> Quy \u0111\u1ed3ng 3 ph\u00e2n s\u1ed1 sau khi r\u00fat g\u1ecdn <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\dfrac{-5^2 - 5 . 3^2}{5^3 + 5^2 . 3^2} = \\dfrac{-5 . (5 + 3^2)}{5^2 . (5 + 3^2)} = \\dfrac{-1}{5}$ <br\/><br\/> $\\begin{align*}& \\dfrac{4^6 . 9^5 + 6^9 . 120}{8^4 . 3^{12} - 6^{11}} \\\\\\\\ &= \\dfrac{(2^2)^6 . (3^2)^5 + (2 . 3)^9 . 2^3 . 3 . 5}{(2^3)^4 . 3^{12} - (2 . 3)^{11}} \\\\\\\\ &= \\dfrac{2^{12} . 3^{10} + 2^9 . 3^9 . 2^3 . 3 . 5}{2^{12} . 3^{12} - 2^{11} . 3^{11}} \\\\\\\\ &= \\dfrac{2^{12} . 3^{10} + 2^{12} . 3^{10} . 5}{2^{11} . (2 . 3^{12} - 1)} \\\\\\\\ &= \\dfrac{2^{12} . 3^{10} . (1 + 5)}{2^{11} . 3^{11} . (2 . 3 - 1)} \\\\\\\\ &= \\dfrac{2 . 6}{3 . 5} = \\dfrac{4}{5} \\end{align*}$ <br\/> $\\begin{align*}& \\dfrac{2929 - 101}{2 . 1919 + 404} = \\dfrac{101 . (29 - 1)}{2 . 19 . 101 + 4 . 101} = \\dfrac{101 . 28}{101 . (38 + 4)} = \\dfrac{2}{3} \\end{align*}$ <br\/> Quy \u0111\u1ed3ng m\u1eabu s\u1ed1 c\u00e1c ph\u00e2n s\u1ed1 tr\u00ean ta \u0111\u01b0\u1ee3c: <br\/> $\\dfrac{-1}{5} = \\dfrac{-1 . 3}{5 . 3} = \\dfrac{-3}{15}$ <br\/> $\\dfrac{4}{5} = \\dfrac{4 . 3}{5 . 3} = \\dfrac{12}{15}$ <br\/> $\\dfrac{2}{3} = \\dfrac{2 . 5}{3 . 5} = \\dfrac{10}{15}$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: C. $\\dfrac{-3}{15}; \\dfrac{12}{15}; \\dfrac{10}{15}$ <\/span>","column":2}]}],"id_ques":1541},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":10,"ques":" Cho 2 ph\u00e2n s\u1ed1 $\\dfrac{2^5 . 7 + 2^5}{2^5 . 5^2 - 2^5 . 3}; \\dfrac{3^4 . 5 - 3^6}{3^4 . 13 + 3^4}$ <br\/> Sau khi r\u00fat g\u1ecdn v\u00e0 quy \u0111\u1ed3ng ta \u0111\u01b0\u1ee3c 2 ph\u00e2n s\u1ed1 n\u00e0o?","select":["A. $\\dfrac{4}{77}; \\dfrac{-2}{77}$","B. $\\dfrac{28}{77}; \\dfrac{-2}{77}$","C. $\\dfrac{28}{77}; \\dfrac{-22}{77}$","D. $\\dfrac{4}{77}; \\dfrac{-22}{77}$ "],"hint":"","explain":"<span class='basic_left'> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\begin{align*}& \\dfrac{2^5 . 7 + 2^5}{2^5 . 5^2 - 2^5 . 3} \\\\ &= \\dfrac{2^5 . (7 + 1)}{2^5 . (5^2 - 3)} \\\\ & = \\dfrac{8}{25 - 3} \\\\ &= \\dfrac{8}{22} \\\\ &= \\dfrac{4}{11} \\end{align*}$ <br\/> $\\begin{align*}& \\dfrac{3^4 . 5 - 3^6}{3^4 . 13 + 3^4} \\\\ &= \\dfrac{3^4 . (5 - 3^2)}{3^4 . (13 + 1)} \\\\ &= \\dfrac{5 - 9}{14} \\\\ &= \\dfrac{-2}{7} \\end{align*}$ <br\/> Quy \u0111\u1ed3ng hai ph\u00e2n s\u1ed1 tr\u00ean ta \u0111\u01b0\u1ee3c: <br\/> $\\dfrac{-2}{7} = \\dfrac{-2 . 11}{7 . 11} = \\dfrac{-22}{77}$ <br\/> $\\dfrac{4}{11} = \\dfrac{4 . 7}{11 . 7} = \\dfrac{28}{77}$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: C. $\\dfrac{28}{77}; \\dfrac{-22}{77}$ <\/span>","column":2}]}],"id_ques":1542},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["<"]]],"list":[{"point":10,"width":50,"type_input":"","ques":"H\u00e3y \u0111i\u1ec1n d\u1ea5u (>, < ho\u1eb7c =) th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng <br\/> $\\dfrac{2003 . 2004 - 1}{2003 . 2004}$ _input_ $\\dfrac{2004 . 2005 - 1}{2004 . 2005}$","hint":"S\u1eed d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p so s\u00e1nh ph\u1ea7n b\u00f9","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch hai ph\u00e2n s\u1ed1 tr\u00ean th\u00e0nh $1 - \\dfrac{a}{b}$ v\u00e0 $1 - \\dfrac{c}{d}$ <br\/> <b> B\u01b0\u1edbc 2: <\/b> So s\u00e1nh $\\dfrac{a}{b}$ v\u00e0 $\\dfrac{c}{d}$ <br\/> <b> B\u01b0\u1edbc 3: <\/b> So s\u00e1nh $1 - \\dfrac{a}{b}$ v\u00e0 $1 - \\dfrac{c}{d}$ <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> $\\dfrac{2003 . 2004 - 1}{2003 . 2004} = \\dfrac{2003 . 20004}{2003. 2004} - \\dfrac{1}{2003 . 2004} = 1 - \\dfrac{1}{2003 . 2004}$ <br\/> $\\dfrac{2004 . 2005 - 1}{2004 . 2005} = \\dfrac{2004 . 2005}{2004 . 2005} - \\dfrac{1}{2004 . 2005} = 1 - \\dfrac{1}{2004 . 2005}$ <br\/> V\u00ec $\\dfrac{1}{2003 . 2004} > \\dfrac{1}{2004 . 2005}$ <br\/> N\u00ean $1 - \\dfrac{1}{2004 . 2005} > 1 - \\dfrac{1}{2003 . 2004}$ <br\/> Hay $\\dfrac{2003 . 2004 - 1}{2003 . 2004} < \\dfrac{2004 . 2005 - 1}{2004 . 2005}$ <br\/> <span class='basic_pink'> V\u1eady ph\u00e2n d\u1ea5u c\u1ea7n \u0111i\u1ec1n l\u00e0: < <\/span> "}]}],"id_ques":1543},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":10,"ques":"H\u00e3y so s\u00e1nh ph\u00e2n s\u1ed1 sau b\u1eb1ng c\u00e1ch s\u1eed d\u1ee5ng ph\u00e2n s\u1ed1 trung gian. <br\/> $\\dfrac{58}{89}$ <span class='basic_hoi_black'>?<\/span> $\\dfrac{36}{53}$","select":["A. >","B. <","C. = "],"hint":"S\u1eed d\u1ee5ng ph\u00e2n s\u1ed1 trung gian l\u00e0 $\\dfrac{2}{3}$","explain":" <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> V\u00ec c\u1ea3 hai ph\u00e2n s\u1ed1 $\\dfrac{58}{89}$ v\u00e0 $\\dfrac{36}{53}$ \u0111\u1ec1u g\u1ea7n b\u1eb1ng ph\u00e2n s\u1ed1 $\\dfrac{2}{3}$ n\u00ean ta d\u00f9ng ph\u00e2n s\u1ed1 $\\dfrac{2}{3}$ l\u00e0m ph\u00e2n s\u1ed1 trung gian <br\/> $\\dfrac{58}{89} = \\dfrac{58 . 2}{89 . 2} = \\dfrac{116}{178} < \\dfrac{116}{174} = \\dfrac{2}{3}$ (1) <br\/> $\\dfrac{36}{53} = \\dfrac{36 . 2}{53 . 2} = \\dfrac{72}{106} > \\dfrac{72}{108} = \\dfrac{2}{3}$ (2) <br\/> T\u1eeb (1) v\u00e0 (2) $\\Rightarrow$ $\\dfrac{58}{89} < \\dfrac{36}{53}$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B. < <\/span>","column":3}]}],"id_ques":1544},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":10,"ques":"H\u00e3y ch\u1ecdn d\u1ea5u th\u00edch h\u1ee3p thay cho d\u1ea5u <span class='basic_hoi_black'>?<\/span> <br\/> $\\left( \\dfrac{1}{80}\\right)^7$ <span class='basic_hoi_black'>?<\/span> $\\left( \\dfrac{1}{243}\\right)^6$","select":["A. >","B. <","C. = "],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/><b> B\u01b0\u1edbc 1: <\/b> So s\u00e1nh $\\left( \\dfrac{1}{80}\\right)^7$ v\u1edbi $\\left( \\dfrac{1}{81}\\right)^7$ r\u1ed3i bi\u1ebfn \u0111\u1ed5i 81 v\u1ec1 l\u0169y th\u1eeba c\u01a1 s\u1ed1 3 <br\/> <b> B\u01b0\u1edbc 2: <\/b> Bi\u1ebfn \u0111\u1ed5i m\u1eabu s\u1ed1 c\u1ee7a ph\u00e2n s\u1ed1 $\\left( \\dfrac{1}{243}\\right)^6$ v\u1ec1 l\u0169y th\u1eeba c\u01a1 s\u1ed1 3 <br\/> <b> B\u01b0\u1edbc 3: <\/b> So s\u00e1nh hai ph\u00e2n s\u1ed1 tr\u00ean v\u1edbi nhau r\u1ed3i k\u1ebft lu\u1eadn <\/span> <br\/><br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> V\u00ec: $\\dfrac{1}{80} > \\dfrac{1}{81}$ n\u00ean $\\left( \\dfrac{1}{80}\\right)^7 > \\left( \\dfrac{1}{81}\\right)^7$ <br\/> $\\left( \\dfrac{1}{81}\\right)^7 = \\left(\\dfrac{1}{3^4}\\right)^7 = \\left( \\dfrac{1}{(3^4)^7}\\right) = \\dfrac{1}{3^{28}}$ <br\/> $\\left( \\dfrac{1}{243}\\right)^6 = \\dfrac{1}{(3^5)^6} = \\dfrac{1}{3^{30}}$ <br\/> V\u00ec $\\dfrac{1}{3^{28}} > \\dfrac{1}{3^{30}}$ n\u00ean $\\left( \\dfrac{1}{81}\\right)^7 > \\left( \\dfrac{1}{243}\\right)^6$ <br\/>$\\Rightarrow$ $\\left( \\dfrac{1}{80}\\right)^7 > \\left( \\dfrac{1}{243}\\right)^6$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A. > <\/span>","column":3}]}],"id_ques":1545},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":10,"ques":" Cho $M = \\dfrac{1}{2} . \\dfrac{3}{4} . \\dfrac{5}{6}. ... .\\dfrac{99}{100}$; $N = \\dfrac{2}{3} . \\dfrac{4}{5}. \\dfrac{6}{7}. ... . \\dfrac{100}{101}$ <br\/> Kh\u1eb3ng \u0111\u1ecbnh n\u00e0o sau \u0111\u00e2y \u0111\u00fang? ","select":["A. M > N","B. M < N","C. M = N "],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/><b> B\u01b0\u1edbc 1: <\/b> X\u00e9t xem M c\u00f3 bao nhi\u00eau th\u1eeba s\u1ed1 v\u00e0 N c\u00f3 bao nhi\u00eau th\u1eeba s\u1ed1 <br\/> <b> B\u01b0\u1edbc 2: <\/b> So s\u00e1nh l\u1ea7n l\u01b0\u1ee3t m\u1ed9t th\u1eeba s\u1ed1 c\u1ee7a M v\u1edbi m\u1ed9t th\u1eeba s\u1ed1 c\u1ee7a N <br\/> So s\u00e1nh $\\dfrac{1}{2}$ v\u00e0 $\\dfrac{2}{3}$; $\\dfrac{3}{4}$ v\u00e0 $\\dfrac{4}{5}$ <br\/> L\u00e0m t\u01b0\u01a1ng t\u1ef1 \u0111\u1ebfn h\u1ebft <br\/> <b> B\u01b0\u1edbc 3: <\/b> So s\u00e1nh M v\u00e0 N <\/span> <br\/><br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> X\u00e9t bi\u1ec3u th\u1ee9c $M = \\dfrac{1}{2} . \\dfrac{3}{4} . \\dfrac{5}{6}. ... .\\dfrac{99}{100}$ <br\/> M c\u00f3 s\u1ed1 th\u1eeba s\u1ed1 l\u00e0: (99 - 1): 2 + 1 = 45 (th\u1eeba s\u1ed1) <br\/> Bi\u1ec3u th\u1ee9c $N = \\dfrac{2}{3} . \\dfrac{4}{5}. \\dfrac{6}{7}. ... . \\dfrac{100}{101}$ <br\/> N c\u00f3 s\u1ed1 th\u1eeba s\u1ed1 l\u00e0: (100 - 2): 2 + 1 = 45 (th\u1eeba s\u1ed1) <br\/> So s\u00e1nh l\u1ea7n l\u01b0\u1ee3t m\u1ed9t th\u1eeba s\u1ed1 c\u1ee7a M v\u1edbi 1 th\u1eeba s\u1ed1 c\u1ee7a N ta c\u00f3 <br\/> $\\dfrac{1}{2} < \\dfrac{2}{3}$ <br\/> $\\dfrac{3}{4} < \\dfrac{4}{5}$ <br\/> $\\dfrac{5}{6} < \\dfrac{6}{7}$ <br\/> ..... <br\/> $\\dfrac{99}{100} < \\dfrac{100}{101}$ <br\/> $\\Rightarrow$ $\\dfrac{1}{2} . \\dfrac{3}{4} . \\dfrac{5}{6}. ... .\\dfrac{99}{100} < \\dfrac{2}{3} . \\dfrac{4}{5}. \\dfrac{6}{7}. ... . \\dfrac{100}{101}$ <br\/> Hay M < N<br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B. M < N <\/span>","column":3}]}],"id_ques":1546},{"time":24,"part":[{"title":"","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":10,"ques":"Kh\u1eb3ng \u0111\u1ecbnh n\u00e0o sau \u0111\u00e2y \u0111\u00fang? ","select":["A. $\\dfrac{134}{43} < \\dfrac{55}{21} < \\dfrac{77}{19} < \\dfrac{116}{37}$","B. $\\dfrac{55}{51} < \\dfrac{77}{19} < \\dfrac{116}{37} < \\dfrac{134}{43}$","C. $\\dfrac{55}{21} < \\dfrac{134}{43} < \\dfrac{116}{37} < \\dfrac{77}{19}$ ","D. $\\dfrac{77}{19} < \\dfrac{55}{21} < \\dfrac{134}{43} < \\dfrac{116}{37}$ "],"hint":"Vi\u1ebft c\u00e1c ph\u00e2n s\u1ed1 tr\u00ean d\u01b0\u1edbi d\u1ea1ng h\u1ed7n s\u1ed1 r\u1ed3i so s\u00e1nh","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>V\u00ec c\u00e1c ph\u00e2n s\u1ed1 tr\u00ean \u0111\u1ec1u l\u1edbn h\u01a1n 1 n\u00ean <br\/> <b> B\u01b0\u1edbc 1: <\/b> Vi\u1ebft m\u1ed7i ph\u00e2n s\u1ed1 tr\u00ean d\u01b0\u1edbi d\u1ea1ng h\u1ed7n s\u1ed1 <br\/> <b> B\u01b0\u1edbc 2: <\/b> So s\u00e1nh c\u00e1c ph\u1ea7n nguy\u00ean c\u1ee7a c\u00e1c ph\u00e2n s\u1ed1 tr\u00ean <br\/> N\u1ebfu c\u00e1c ph\u00e2n s\u1ed1 c\u00f3 ph\u1ea7n nguy\u00ean b\u1eb1ng nhau th\u00ec ta so s\u00e1nh \u0111\u1ebfn ph\u1ea7n ph\u00e2n s\u1ed1 <br\/> <b> B\u01b0\u1edbc 3: <\/b> S\u1eafp x\u1ebfp c\u00e1c ph\u00e2n s\u1ed1 \u0111\u00f3 theo th\u1ee9 t\u1ef1 t\u1eeb nh\u1ecf \u0111\u1ebfn l\u1edbn <\/span> <br\/><br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> Ta c\u00f3: $\\dfrac{134}{43} = 3 \\dfrac{5}{43}$; $\\dfrac{77}{19} = 4 \\dfrac{1}{19}$ <br\/> $\\dfrac{55}{21} = 2 \\dfrac{13}{21}$; $\\dfrac{116}{37} = 3 \\dfrac{5}{37}$ <br\/> V\u00ec 3 = 3 n\u00ean ta so s\u00e1nh $\\dfrac{5}{37}$ v\u1edbi $\\dfrac{5}{43}$ <br\/> C\u00f3: $\\dfrac{5}{37} > \\dfrac{5}{43}$ $\\Rightarrow$ $3 \\dfrac{5}{37} > 3 \\dfrac{5}{43}$ <br\/> $\\Rightarrow$ $2 \\dfrac{13}{21} < 3 \\dfrac{5}{43} < 3 \\dfrac{5}{37} < 4 \\dfrac{1}{19}$ <br\/> Hay $\\dfrac{55}{21} < \\dfrac{134}{43} < \\dfrac{116}{37} < \\dfrac{77}{19}$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: C <\/span>","column":2}]}],"id_ques":1547},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["4"],["5"]]],"list":[{"point":10,"width":50,"type_input":"","ques":"T\u00ecm ph\u00e2n s\u1ed1 c\u00f3 t\u1eed s\u1ed1 b\u1eb1ng 4, bi\u1ebft ph\u00e2n s\u1ed1 \u0111\u00f3 l\u1edbn h\u01a1n $\\dfrac{13}{17}$ v\u00e0 nh\u1ecf h\u01a1n $\\dfrac{13}{15}$ <br\/> \u0110\u00e1p \u00e1n l\u00e0:<div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":"Quy \u0111\u1ed3ng t\u1eed s\u1ed1 r\u1ed3i t\u00ecm m\u1eabu s\u1ed1 c\u1ee7a ph\u00e2n s\u1ed1 \u0111\u00f3","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b>G\u1ecdi ph\u00e2n s\u1ed1 c\u1ea7n t\u00ecm l\u00e0 $\\dfrac{4}{x}$ <br\/> Theo \u0111\u1ec1 b\u00e0i ta c\u00f3: $\\dfrac{13}{17} < \\dfrac{4}{x} < \\dfrac{13}{15}$ <br\/> <b> B\u01b0\u1edbc 2: <\/b> Quy \u0111\u1ed3ng t\u1eed s\u1ed1 c\u00e1c ph\u00e2n s\u1ed1 tr\u00ean <br\/> <b> B\u01b0\u1edbc 3: <\/b> T\u00ecm x th\u1ecfa m\u00e3n y\u00eau c\u1ea7n \u0111\u1ec1 b\u00e0i <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> G\u1ecdi ph\u00e2n s\u1ed1 c\u1ea7n t\u00ecm l\u00e0 $\\dfrac{4}{x}$ ($x \\in \\mathbb{Z}, x \\neq 0$) <br\/> V\u00ec ph\u00e2n s\u1ed1 \u0111\u00f3 l\u1edbn h\u01a1n $\\dfrac{13}{17}$ v\u00e0 nh\u1ecf h\u01a1n $\\dfrac{13}{15}$ n\u00ean ta c\u00f3: <br\/> $\\dfrac{13}{17} < \\dfrac{4}{x} < \\dfrac{13}{15}$ <br\/> Quy \u0111\u1ed3ng t\u1eed s\u1ed1 ta \u0111\u01b0\u1ee3c: $\\dfrac{52}{68} < \\dfrac{52}{13x} < \\dfrac{52}{60}$ <br\/> $\\Rightarrow$ 60 < 13x < 68 <br\/> V\u1edbi 13x = 61 $\\Rightarrow$ $x = \\dfrac{61}{13}$ (lo\u1ea1i) <br\/> V\u1edbi 13x = 62 $\\Rightarrow$ $x = \\dfrac{62}{13}$ (lo\u1ea1i) <br\/> V\u1edbi 13x = 63 $\\Rightarrow$ $x = \\dfrac{63}{13}$ (lo\u1ea1i) <br\/> V\u1edbi 13x = 64 $\\Rightarrow$ $x = \\dfrac{64}{13}$ (lo\u1ea1i) <br\/> V\u1edbi 13x = 65 $\\Rightarrow$ x = 5 <b> (th\u1ecfa m\u00e3n) <\/b> <br\/> V\u1edbi 13x = 66 $\\Rightarrow$ $x = \\dfrac{66}{13}$ (lo\u1ea1i) <br\/> V\u1edbi 13x = 67 $\\Rightarrow$ $x = \\dfrac{67}{13}$ (lo\u1ea1i) <br\/> <span class='basic_pink'> V\u1eady ph\u00e2n s\u1ed1 c\u1ea7n t\u00ecm l\u00e0: $\\dfrac{4}{5}$<\/span> "}]}],"id_ques":1548},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["9","10"],["30"]]],"list":[{"point":10,"width":50,"type_input":"","input_hint":["frac"],"ques":"T\u00ecm ph\u00e2n s\u1ed1 c\u00f3 m\u1eabu s\u1ed1 l\u00e0 30, bi\u1ebft ph\u00e2n s\u1ed1 \u0111\u00f3 l\u1edbn h\u01a1n $\\dfrac{5}{17}$ v\u00e0 nh\u1ecf h\u01a1n $\\dfrac{6}{17}$ <br\/> \u0110\u00e1p \u00e1n l\u00e0: <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":"Quy \u0111\u1ed3ng m\u1eabu s\u1ed1 r\u1ed3i t\u00ecm t\u1eed s\u1ed1 c\u1ee7a ph\u00e2n s\u1ed1 \u0111\u00f3","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b>G\u1ecdi ph\u00e2n s\u1ed1 c\u1ea7n t\u00ecm l\u00e0 $\\dfrac{a}{30}$ <br\/> Theo \u0111\u1ec1 b\u00e0i ta c\u00f3: $\\dfrac{5}{17} < \\dfrac{a}{30} < \\dfrac{6}{17}$ <br\/> <b> B\u01b0\u1edbc 2: <\/b> Quy \u0111\u1ed3ng m\u1eabu s\u1ed1 c\u00e1c ph\u00e2n s\u1ed1 tr\u00ean <br\/> <b> B\u01b0\u1edbc 3: <\/b> T\u00ecm a th\u1ecfa m\u00e3n y\u00eau c\u1ea7n \u0111\u1ec1 b\u00e0i <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> G\u1ecdi ph\u00e2n s\u1ed1 c\u1ea7n t\u00ecm l\u00e0 $\\dfrac{a}{30}$ ($a \\in \\mathbb{Z}, a \\neq 0$) <br\/> V\u00ec ph\u00e2n s\u1ed1 \u0111\u00f3 l\u1edbn h\u01a1n $\\dfrac{5}{17}$ v\u00e0 nh\u1ecf h\u01a1n $\\dfrac{6}{17}$ n\u00ean ta c\u00f3: <br\/> $\\dfrac{5}{17} < \\dfrac{a}{30} < \\dfrac{6}{17}$ <br\/> Quy \u0111\u1ed3ng m\u1eabu s\u1ed1 ta \u0111\u01b0\u1ee3c: $\\dfrac{150}{510} < \\dfrac{17a}{510} < \\dfrac{180}{510}$ <br\/> $\\Rightarrow$ 150 < 17a < 180 hay 17a $\\in$ {151, 152, 153, ..., 179} <br\/> Th\u1eed l\u1ea7n l\u01b0\u1ee3t c\u00e1c gi\u00e1 tr\u1ecb ta th\u1ea5y ch\u1ec9 c\u00f3 17a = 153 $\\Rightarrow$ a = 9 (th\u1ecfa m\u00e3n) <br\/> V\u00e0 17a = 170 $\\Rightarrow$ a = 10 (th\u1ecfa m\u00e3n) ngo\u00e0i ra kh\u00f4ng c\u00f2n gi\u00e1 tr\u1ecb n\u00e0o th\u1ecfa m\u00e3n"}]}],"id_ques":1549},{"time":24,"part":[{"title":"Ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"select":["A. $\\dfrac{3}{4}$","B. $\\dfrac{2}{3}$","C. $1$"],"ques":"R\u00fat g\u1ecdn ph\u00e2n s\u1ed1 sau: <br\/> $\\dfrac{244 . 395 - 151}{244 + 395 . 243}$ = ?","hint":"Vi\u1ebft 244 \u1edf t\u1eed th\u00e0nh 243 + 1","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b>Vi\u1ebft 244 \u1edf t\u1eed th\u00e0nh 243 + 1 <br\/> <b> B\u01b0\u1edbc 2: <\/b> Nh\u00e2n ph\u00e1 ngo\u1eb7c, r\u1ed3i bi\u1ebfn \u0111\u1ed5i \u1edf t\u1eed s\u1ed1 \u0111\u1ec3 \u0111\u01b0\u1ee3c bi\u1ec3u th\u1ee9c gi\u1ed1ng m\u1eabu s\u1ed1 <br\/> <b> B\u01b0\u1edbc 3: <\/b> R\u00fat g\u1ecdn <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> $\\dfrac{244 . 395 - 151}{244 + 395 . 243} \\\\ = \\dfrac{(243 + 1) . 395 - 151}{244 + 395 . 243} \\\\ = \\dfrac{243 . 395 + 395 - 151}{244 + 395 . 243} \\\\ = \\dfrac{243 . 395 + 244}{244 + 395 . 243} \\\\ = 1$"}]}],"id_ques":1550}],"lesson":{"save":0,"level":3}}