{"segment":[{"time":24,"part":[{"time":3,"title":"N\u1ed1i t\u1eeb ho\u1eb7c c\u1ee5m t\u1eeb \u1edf c\u1ed9t b\u00ean tr\u00e1i v\u1edbi c\u1ed9t b\u00ean ph\u1ea3i \u0111\u1ec3 \u0111\u01b0\u1ee3c c\u00e2u ho\u00e0n ch\u1ec9nh","title_trans":"","audio":"","temp":"matching","correct":[["2","3","1"]],"list":[{"point":5,"image":"","left":["Hai \u0111\u01b0\u1eddng tr\u00f2n $(O;R)$ v\u00e0 $(O';r)$ ti\u1ebfp x\u00fac ngo\u00e0i nhau th\u00ec","Hai \u0111\u01b0\u1eddng tr\u00f2n $(O;R)$ v\u00e0 $(O';r)$ c\u1eaft nhau t\u1ea1i hai \u0111i\u1ec3m ph\u00e2n bi\u1ec7t th\u00ec","Hai \u0111\u01b0\u1eddng tr\u00f2n $(O;R)$ v\u00e0 $(O';r)$ \u1edf ngo\u00e0i nhau"],"right":["$OO' > R+r$","$OO' = R+r$","$OO' < R+r$"],"top":100,"hint":"","explain":"<span class='basic_left'>Hai \u0111\u01b0\u1eddng tr\u00f2n $(O;R)$ v\u00e0 $(O';r)$ ti\u1ebfp x\u00fac ngo\u00e0i nhau $\\Rightarrow OO'=R+r$ <br\/> Hai \u0111\u01b0\u1eddng tr\u00f2n $(O;R)$ v\u00e0 $(O';r)$ c\u1eaft nhau t\u1ea1i hai \u0111i\u1ec3m ph\u00e2n bi\u1ec7t $\\Rightarrow OO' < R + r $ <br\/> Hai \u0111\u01b0\u1eddng tr\u00f2n $(O;R)$ v\u00e0 $(O';r)$ \u1edf ngo\u00e0i nhau $\\Rightarrow OO' > R + r $ <\/span>"}]}],"id_ques":1211},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"<span class='basic_left'>Trong h\u1ec7 tr\u1ee5c t\u1ecda \u0111\u1ed9 $Oxy$, cho \u0111\u01b0\u1eddng tr\u00f2n t\u00e2m $I(1;3)$, b\u00e1n k\u00ednh b\u1eb1ng $4$ v\u00e0 \u0111\u01b0\u1eddng tr\u00f2n t\u00e2m $H(1;-3)$ b\u00e1n k\u00ednh b\u1eb1ng $2$. H\u00e3y x\u00e1c \u0111\u1ecbnh v\u1ecb tr\u00ed t\u01b0\u01a1ng \u0111\u1ed1i c\u1ee7a hai \u0111\u01b0\u1eddng tr\u00f2n.<\/span>","select":["A. Hai \u0111\u01b0\u1eddng tr\u00f2n ti\u1ebfp x\u00fac trong nhau ","B. Hai \u0111\u01b0\u1eddng tr\u00f2n c\u1eaft nhau t\u1ea1i hai \u0111i\u1ec3m ph\u00e2n bi\u1ec7t","C. Hai \u0111\u01b0\u1eddng tr\u00f2n ti\u1ebfp x\u00fac ngo\u00e0i nhau","D. Hai \u0111\u01b0\u1eddng tr\u00f2n \u0111\u1ef1ng nhau"],"hint":"L\u1ea5y hai \u0111i\u1ec3m $I$ v\u00e0 $H$ tr\u00ean h\u1ec7 tr\u1ee5c t\u1ecda \u0111\u1ed9 r\u1ed3i v\u1ebd hai \u0111\u01b0\u1eddng tr\u00f2n","explain":"<span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D12.png' \/><\/center> D\u1ec5 th\u1ea5y hai \u0111\u01b0\u1eddng tr\u00f2n ti\u1ebfp x\u00fac ngo\u00e0i nhau <br\/><br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 C. <\/span><\/span>","column":1}]}],"id_ques":1212},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"Hai \u0111\u01b0\u1eddng tr\u00f2n \u0111\u1ed3ng t\u00e2m l\u00e0:","select":["A. Hai \u0111\u01b0\u1eddng tr\u00f2n c\u00f3 c\u00f9ng b\u00e1n k\u00ednh ","B. Hai \u0111\u01b0\u1eddng tr\u00f2n ph\u00e2n bi\u1ec7t c\u1eaft nhau","C. Hai \u0111\u01b0\u1eddng tr\u00f2n c\u00f3 c\u00f9ng t\u00e2m","D. Hai \u0111\u01b0\u1eddng tr\u00f2n ti\u1ebfp x\u00fac nhau t\u1ea1i m\u1ed9t \u0111i\u1ec3m"],"explain":" V\u00ec \u0111\u1ed3ng l\u00e0 c\u00f9ng n\u00ean hai \u0111\u01b0\u1eddng tr\u00f2n \u0111\u1ed3ng t\u00e2m l\u00e0 hai \u0111\u01b0\u1eddng tr\u00f2n c\u00f3 c\u00f9ng t\u00e2m<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 C. <\/span>","column":1}]}],"id_ques":1213},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"\u0110\u1ec1 chung cho hai c\u00e2u","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"<span class='basic_left'>Cho \u0111o\u1ea1n th\u1eb3ng $MN$ d\u00e0i $5cm$, v\u1ebd \u0111\u01b0\u1eddng tr\u00f2n $(M; 2cm)$. \u0110\u01b0\u1eddng tr\u00f2n t\u00e2m $N$ ti\u1ebfp x\u00fac ngo\u00e0i v\u1edbi \u0111\u01b0\u1eddng tr\u00f2n $(M)$ c\u00f3 b\u00e1n k\u00ednh l\u00e0:<\/span>","select":["A. $3cm$ ","B. $7cm$","C. $12cm$","D. $11cm$"],"explain":"<span class='basic_left'><center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D11.png' \/><\/center>G\u1ecdi $I$ l\u00e0 ti\u1ebfp \u0111i\u1ec3m c\u1ee7a 2 \u0111\u01b0\u1eddng tr\u00f2n<br\/> Ta c\u00f3: $MN=5cm;\\, MI =2cm$ <br\/>V\u00ec $(M)$ v\u00e0 $(N)$ ti\u1ebfp x\u00fac nhau n\u00ean ta c\u00f3: $MI + IN = MN $<br\/> $\\Rightarrow NI = NM - MI$$ = 5 - 2 = 3\\, (cm)$<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 A. <\/span><\/span>","column":4}]}],"id_ques":1214},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"\u0110\u1ec1 chung cho hai c\u00e2u","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"<span class='basic_left'>Cho \u0111o\u1ea1n th\u1eb3ng $MN$ d\u00e0i $5cm$, v\u1ebd \u0111\u01b0\u1eddng tr\u00f2n $(M; 2cm)$. \u0110\u01b0\u1eddng tr\u00f2n t\u00e2m $N$ ti\u1ebfp x\u00fac trong v\u1edbi \u0111\u01b0\u1eddng tr\u00f2n $(M)$ c\u00f3 b\u00e1n k\u00ednh l\u00e0:<\/span>","select":["A. $3cm$ ","B. $7cm$","C. $12cm$","D. $11cm$"],"explain":"<span class='basic_left'><center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D11.1.png' \/><\/center>G\u1ecdi $I$ l\u00e0 ti\u1ebfp \u0111i\u1ec3m c\u1ee7a $(M)$ v\u00e0 $(N).$ <br\/> Ta c\u00f3: $MI=2cm;\\,MN=5cm$ <br\/>V\u00ec $(N)$ ti\u1ebfp x\u00fac trong v\u1edbi $(M)$ n\u00ean ta c\u00f3: $MN = IN - IM$ <br\/> $\\Rightarrow NI=NM+MI$$=5+2=7\\, (cm)$<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 B. <\/span><\/span>","column":4}]}],"id_ques":1215},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"<span class='basic_left'> Hai \u0111\u01b0\u1eddng tr\u00f2n tr\u00f9ng nhau c\u00f3 bao nhi\u00eau \u0111i\u1ec3m chung? <\/span>","select":["A. 2 \u0111i\u1ec3m ","B. 1 \u0111i\u1ec3m","C. kh\u00f4ng c\u00f3 \u0111i\u1ec3m chung","D. v\u00f4 s\u1ed1 \u0111i\u1ec3m chung "],"explain":"<span class='basic_left'> <\/center>Hai \u0111\u01b0\u1eddng tr\u00f2n tr\u00f9ng nhau c\u00f3 v\u00f4 s\u1ed1 \u0111i\u1ec3m chung<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 D. <\/span><\/span>","column":2}]}],"id_ques":1216},{"time":24,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["2"]]],"list":[{"point":5,"width":40,"content":"","type_input":"","ques":"<span class='basic_left'>Cho hai \u0111\u01b0\u1eddng tr\u00f2n $(O;4cm)$ v\u00e0 \u0111\u01b0\u1eddng tr\u00f2n $(I)$ ti\u1ebfp x\u00fac trong. Bi\u1ebft kho\u1ea3ng c\u00e1ch gi\u1eefa hai t\u00e2m b\u1eb1ng $2cm$. T\u00ednh b\u00e1n k\u00ednh $r$ c\u1ee7a \u0111\u01b0\u1eddng tr\u00f2n $(I)$.<br\/><b>\u0110\u00e1p \u00e1n:<\/b> $r =$_input_ $(cm)$ <\/span>","hint":"","explain":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D2.png' \/><\/center><span class='basic_left'> G\u1ecdi $R$ l\u00e0 b\u00e1n k\u00ednh \u0111\u01b0\u1eddng tr\u00f2n l\u1edbn, $r$ l\u00e0 b\u00e1n k\u00ednh \u0111\u01b0\u1eddng tr\u00f2n nh\u1ecf <br\/> V\u00ec $(O)$ v\u00e0 $(I)$ ti\u1ebfp x\u00fac trong n\u00ean: $OI = R - r$ <br\/> $\\Rightarrow r =R - OI$ <br\/> $= 4-2$ <br\/> $=2\\,(cm)$ <br\/> <span class='basic_pink'>V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u00e0 $2.$<\/span><\/span>"}]}],"id_ques":1217},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"<span class='basic_left'>Cho hai \u0111\u01b0\u1eddng tr\u00f2n t\u00e2m $O$ v\u00e0 $O'$ c\u1eaft nhau t\u1ea1i hai \u0111i\u1ec3m $E$ v\u00e0 $F$. Kh\u1eb3ng \u0111\u1ecbnh n\u00e0o sau \u0111\u00e2y l\u00e0 \u0111\u00fang?<\/span>","select":["A. $OO'$ l\u00e0 trung tr\u1ef1c c\u1ee7a $EF$ ","B. $EF$ l\u00e0 trung tr\u1ef1c c\u1ee7a $OO'$","C. $OE$ l\u00e0 trung tr\u1ef1c c\u1ee7a $O'F$","D. $OF$ l\u00e0 trung tr\u1ef1c c\u1ee7a $EO'$"],"explain":"<span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D10.png' \/><\/center>Ta c\u00f3: $OO'$ l\u00e0 \u0111\u01b0\u1eddng n\u1ed1i t\u00e2m; $EF$ l\u00e0 d\u00e2y chung <br\/> V\u1eady $OO'$ l\u00e0 trung tr\u1ef1c c\u1ee7a $EF$ (t\u00ednh ch\u1ea5t \u0111\u01b0\u1eddng n\u1ed1i t\u00e2m) <br\/>Suy ra \u0111\u00e1p \u00e1n A \u0111\u00fang <br\/> $EF$ l\u00e0 trung tr\u1ef1c c\u1ee7a $OO'$ n\u1ebfu v\u00e0 ch\u1ec9 n\u1ebfu $H$ l\u00e0 trung \u0111i\u1ec3m c\u1ee7a $OO'$ <br\/> $OE$ v\u00e0 $O'F$; $OF$ v\u00e0 $O'E$ ho\u1eb7c l\u00e0 song song ho\u1eb7c l\u00e0 k\u00e9o d\u00e0i c\u1eaft nhau <br\/> V\u1eady \u0111\u00e1p \u00e1n B, C, D kh\u00f4ng \u0111\u00fang <br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 A. <\/span><\/span>","column":2}]}],"id_ques":1218},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"<span class='basic_left'> Hai \u0111\u01b0\u1eddng tr\u00f2n c\u1eaft nhau t\u1ea1i hai \u0111i\u1ec3m ph\u00e2n bi\u1ec7t c\u00f3 s\u1ed1 \u0111\u01b0\u1eddng ti\u1ebfp tuy\u1ebfn chung l\u00e0: <\/span>","select":["A. 1 \u0111\u01b0\u1eddng","B. 2 \u0111\u01b0\u1eddng","C. 3 \u0111\u01b0\u1eddng","C. 4 \u0111\u01b0\u1eddng"],"explain":"<span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D3.png' \/><\/center>Hai \u0111\u01b0\u1eddng tr\u00f2n c\u1eaft nhau t\u1ea1i hai \u0111i\u1ec3m ph\u00e2n bi\u1ec7t c\u00f3 hai \u0111\u01b0\u1eddng ti\u1ebfp tuy\u1ebfn chung<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 B. <\/span><\/span>","column":4}]}],"id_ques":1219},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"<span class='basic_left'> T\u00ecm v\u1ecb tr\u00ed t\u01b0\u01a1ng \u0111\u1ed1i c\u1ee7a hai \u0111\u01b0\u1eddng tr\u00f2n \u0111\u1ec3 ch\u00fang c\u00f3 m\u1ed9t ti\u1ebfp tuy\u1ebfn chung? <\/span>","select":["A. C\u1eaft nhau t\u1ea1i hai \u0111i\u1ec3m ph\u00e2n bi\u1ec7t","B. \u1edf ngo\u00e0i nhau","C. ti\u1ebfp x\u00fac ngo\u00e0i ","D. ti\u1ebfp x\u00fac trong"],"explain":"<span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D3.2.png' \/><\/center><br\/><br\/>Hai \u0111\u01b0\u1eddng tr\u00f2n ti\u1ebfp x\u00fac trong nhau c\u00f3 m\u1ed9t \u0111\u01b0\u1eddng ti\u1ebfp tuy\u1ebfn chung<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 D. <\/span><\/span>","column":2}]}],"id_ques":1220},{"time":24,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["25"]]],"list":[{"point":5,"width":40,"content":"","type_input":"","ques":"<span class='basic_left'>Cho hai \u0111\u01b0\u1eddng tr\u00f2n $(O;20cm)$ v\u00e0 $(O'; 15cm)$ c\u1eaft nhau t\u1ea1i $A$ v\u00e0 $B$. \u0110o\u1ea1n th\u1eb3ng $AB$ c\u1eaft \u0111\u01b0\u1eddng n\u1ed1i t\u00e2m t\u1ea1i $H$. Bi\u1ebft $AB$ b\u1eb1ng $24cm$ ($O$ v\u00e0 $O'$ n\u1eb1m kh\u00e1c ph\u00eda v\u1edbi $AB$). T\u00ednh \u0111\u1ed9 d\u00e0i \u0111o\u1ea1n n\u1ed1i t\u00e2m.<br\/><b>\u0110\u00e1p \u00e1n:<\/b> $OO' =$ _input_ $(cm)$<\/span>","hint":"T\u00ednh \u0111\u1ed9 d\u00e0i c\u00e1c \u0111o\u1ea1n th\u1eb3ng $OH$ v\u00e0 $O'H$ b\u1eb1ng \u0111\u1ecbnh l\u00ed Pitago<br\/> OO' = $OH$ + O'H","explain":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D4.png' \/><\/center><span class='basic_left'>Ta c\u00f3: $OO'$ l\u00e0 trung tr\u1ef1c c\u1ee7a $AB$ (t\u00ednh ch\u1ea5t \u0111\u01b0\u1eddng n\u1ed1i t\u00e2m) <br\/> $\\Rightarrow AH\\bot OO' $;$ AH=\\dfrac{AB}{2}=12cm $ (t\u00ednh ch\u1ea5t \u0111\u01b0\u1eddng trung tr\u1ef1c) <br\/>X\u00e9t $\\Delta OAH$ vu\u00f4ng t\u1ea1i $H$ <br\/> $OA^2 = OH^2 + AH^2$ (\u0111\u1ecbnh l\u00ed Pitago) <br\/> $\\Rightarrow OH=\\sqrt{O{{A}^{2}}-A{{H}^{2}}}$ <br\/> $=\\sqrt{{{20}^{2}}-{{12}^{2}}}$ <br\/>$=16\\,(cm)$<br\/>X\u00e9t $\\Delta AO'H$ vu\u00f4ng t\u1ea1i $H$ <br\/> $O'A^2 = O'H^2 + AH^2$ (\u0111\u1ecbnh l\u00ed Pitago) <br\/> $\\Rightarrow O'H=\\sqrt{O'{{A}^{2}}-A{{H}^{2}}}$ <br\/> $=\\sqrt{{{15}^{2}}-{{12}^{2}}}$ <br\/> $=9\\,(cm)$<br\/> $OO'=OH+O'H$$=16+9=25\\,(cm)$ <br\/> <span class='basic_pink'>V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u00e0 $25.$<\/span><\/span>"}]}],"id_ques":1221},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"<span class='basic_left'>Cho hai \u0111\u01b0\u1eddng tr\u00f2n $(O;17cm)$ v\u00e0 $(I; 10cm)$ c\u1eaft nhau t\u1ea1i $E$ v\u00e0 $F$. \u0110o\u1ea1n th\u1eb3ng $EF$ c\u1eaft \u0111\u01b0\u1eddng n\u1ed1i t\u00e2m t\u1ea1i $H$. Bi\u1ebft $EF$ b\u1eb1ng $16cm$ ($O$ v\u00e0 $I$ n\u1eb1m c\u00f9ng ph\u00eda v\u1edbi $EF$). T\u00ednh \u0111\u1ed9 d\u00e0i \u0111o\u1ea1n n\u1ed1i t\u00e2m.<\/span>","select":["A. $27\\,cm$","B. $7\\,cm$","C. $9\\,cm$","D. $21\\,cm$"],"hint":"T\u00ednh \u0111\u1ed9 d\u00e0i c\u00e1c \u0111o\u1ea1n th\u1eb3ng $OH$ v\u00e0 $IH$ b\u1eb1ng \u0111\u1ecbnh l\u00ed Pitago<br\/> $OI = OH - IH$","explain":"<span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D5.1.png' \/><\/center>Ta c\u00f3: $OH$ l\u00e0 trung tr\u1ef1c c\u1ee7a $EF$ (t\u00ednh ch\u1ea5t \u0111\u01b0\u1eddng n\u1ed1i t\u00e2m) <br\/> $\\Rightarrow EH\\bot OI $;$ EH=\\dfrac{EF}{2}=8\\,(cm) $ (t\u00ednh ch\u1ea5t \u0111\u01b0\u1eddng trung tr\u1ef1c) <br\/>X\u00e9t $\\Delta OEH$ vu\u00f4ng t\u1ea1i $H$ <br\/> $OE^2 = OH^2 + EH^2$ (\u0111\u1ecbnh l\u00ed Pitago) <br\/> $\\Rightarrow OH=\\sqrt{O{{E}^{2}}-E{{H}^{2}}}$ <br\/> $=\\sqrt{{{17}^{2}}-{{8}^{2}}}$<br\/> $=15\\,(cm)$ <br\/>X\u00e9t $\\Delta EIH$ vu\u00f4ng t\u1ea1i $H$ <br\/> $IE^2 = IH^2 + EH^2$ (\u0111\u1ecbnh l\u00ed Pitago) <br\/>$\\Rightarrow IH=\\sqrt{I{{E}^{2}}-E{{H}^{2}}}$ <br\/> $=\\sqrt{{{10}^{2}}-{{8}^{2}}}$ <br\/> $=6\\,(cm)$<br\/> $OI=OH-IH$$=15-6=9\\,(cm)$<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 C. <\/span><\/span>","column":4}]}],"id_ques":1222},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"\u0110\u1ec1 chung cho ba c\u00e2u","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"<span class='basic_left'> Cho hai \u0111\u01b0\u1eddng tr\u00f2n $(O)$ v\u00e0 $(O')$ ti\u1ebfp x\u00fac ngo\u00e0i t\u1ea1i $A$. K\u1ebb ti\u1ebfp tuy\u1ebfn chung ngo\u00e0i $DE$, $D$ thu\u1ed9c $(O)$ v\u00e0 $E$ thu\u1ed9c $(O')$. K\u1ebb ti\u1ebfp tuy\u1ebfn trong t\u1ea1i $A$, c\u1eaft $DE$ t\u1ea1i $I$. G\u1ecdi $M$ l\u00e0 giao \u0111i\u1ec3m c\u1ee7a $OI$ v\u00e0 $AD, N$ l\u00e0 giao \u0111i\u1ec3m c\u1ee7a $O'I$ v\u00e0 $AE$.<br\/><b>C\u00e2u 1:<\/b> T\u1ee9 gi\u00e1c $AMIN$ l\u00e0 h\u00ecnh g\u00ec?<\/span>","select":["A. H\u00ecnh b\u00ecnh h\u00e0nh","B. H\u00ecnh ch\u1eef nh\u1eadt","C. H\u00ecnh thoi","D. H\u00ecnh vu\u00f4ng"],"explain":"<span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D6.png' \/><\/center>Ta c\u00f3 $ID=IA$ (t\u00ednh ch\u1ea5t hai ti\u1ebfp tuy\u1ebfn c\u1eaft nhau) <br\/>$\\Rightarrow I$ n\u1eb1m tr\u00ean \u0111\u01b0\u1eddng trung tr\u1ef1c c\u1ee7a $AD$ <br\/> $OA=OD=R$<br\/> $\\Rightarrow O$ n\u1eb1m tr\u00ean \u0111\u01b0\u1eddng trung tr\u1ef1c c\u1ee7a $AD$ <br\/> $\\Rightarrow OI$ l\u00e0 trung tr\u1ef1c c\u1ee7a $AD$ <br\/> $\\Rightarrow OI\\bot AD$ $\\Rightarrow \\widehat{IMA}={{90}^{o}}$ (1)<br\/> Ch\u1ee9ng minh t\u01b0\u01a1ng t\u1ef1: $\\widehat{INA}={{90}^{o}}$ (2)<br\/> $IO$ l\u00e0 ph\u00e2n gi\u00e1c $\\widehat{DIA}$(t\u00ednh ch\u1ea5t hai ti\u1ebfp tuy\u1ebfn c\u1eaft nhau) <br\/> $IO'$ l\u00e0 ph\u00e2n gi\u00e1c $\\widehat{EIA}$ (t\u00ednh ch\u1ea5t hai ti\u1ebfp tuy\u1ebfn c\u1eaft nhau) <br\/> $\\Rightarrow \\widehat{OIO'}=\\widehat{OIA}+\\widehat{O'IA}$$=\\dfrac{1}{2}\\left(\\widehat{DIA}+\\widehat{EIA}\\right)=\\dfrac{1}{2}\\widehat{DIE}$$={{90}^{o}}$ <br\/> $\\Rightarrow \\widehat{MIN}={{90}^{o}}$ (3) <br\/> T\u1eeb (1), (2), (3) $\\Rightarrow AMIN$ l\u00e0 h\u00ecnh ch\u1eef nh\u1eadt (d\u1ea5u hi\u1ec7u nh\u1eadn bi\u1ebft)<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 B. <\/span><\/span>","column":2}]}],"id_ques":1223},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"\u0110\u1ec1 chung cho ba c\u00e2u","temp":"fill_the_blank","correct":[[["IN","NI"]]],"list":[{"point":5,"width":40,"content":"","type_input":"","ques":"<span class='basic_left'>Cho hai \u0111\u01b0\u1eddng tr\u00f2n $(O)$ v\u00e0 $(O')$ ti\u1ebfp x\u00fac ngo\u00e0i t\u1ea1i $A$. K\u1ebb ti\u1ebfp tuy\u1ebfn chung ngo\u00e0i $DE$, $D$ thu\u1ed9c $(O)$ v\u00e0 $E$ thu\u1ed9c $(O')$. K\u1ebb ti\u1ebfp tuy\u1ebfn trong t\u1ea1i $A$, c\u1eaft $DE$ t\u1ea1i $I$. G\u1ecdi $M$ l\u00e0 giao \u0111i\u1ec3m c\u1ee7a $OI$ v\u00e0 $AD, N$ l\u00e0 giao \u0111i\u1ec3m c\u1ee7a $O'I$ v\u00e0 $AE$.<br\/><b>C\u00e2u 2:<\/b> Ta ch\u1ee9ng minh \u0111\u01b0\u1ee3c r\u1eb1ng $IM.IO$ = $IO'.$ _input_ <\/span>","explain":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D6.1.png' \/><\/center><span class='basic_left'> Ta c\u00f3: $AI$ l\u00e0 ti\u1ebfp tuy\u1ebfn chung c\u1ee7a $(O)$ v\u00e0 $(O')$ <br\/> $\\Rightarrow AI \\bot OO'$ (t\u00ednh ch\u1ea5t) <br\/> X\u00e9t $\\Delta OIO'$ c\u00f3 $\\widehat{I} = 90^o$ (theo c\u00e2u 1) <br\/> $\\Rightarrow MI.OI=A{{I}^{2}}$ (h\u1ec7 th\u1ee9c l\u01b0\u1ee3ng trong tam gi\u00e1c vu\u00f4ng) (1) <br\/> X\u00e9t $\\Delta IAO'$ vu\u00f4ng t\u1ea1i $A$ <br\/> $\\widehat{INA}= 90^o$ (theo c\u00e2u 1) $\\Rightarrow AN\\bot O'I$ <br\/> $\\Rightarrow NI.O'I=A{{I}^{2}}$ (h\u1ec7 th\u1ee9c l\u01b0\u1ee3ng trong tam gi\u00e1c vu\u00f4ng) (2) <br\/> T\u1eeb (1), (2) $\\Rightarrow MI.OI=NI.O'I$ <br\/> <span class='basic_pink'>V\u1eady t\u1eeb c\u1ea7n \u0111i\u1ec1n l\u00e0 $NI.$<\/span><\/span>"}]}],"id_ques":1224},{"time":24,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"\u0110\u1ec1 chung cho ba c\u00e2u","temp":"fill_the_blank","correct":[[["8"]]],"list":[{"point":5,"width":40,"content":"","type_input":"","ques":"<span class='basic_left'>Cho hai \u0111\u01b0\u1eddng tr\u00f2n $(O)$ v\u00e0 $(O')$ ti\u1ebfp x\u00fac ngo\u00e0i t\u1ea1i $A$. K\u1ebb ti\u1ebfp tuy\u1ebfn chung ngo\u00e0i $DE$, $D$ thu\u1ed9c $(O)$ v\u00e0 $E$ thu\u1ed9c $(O')$. K\u1ebb ti\u1ebfp tuy\u1ebfn trong t\u1ea1i $A$, c\u1eaft $DE$ t\u1ea1i $I$. G\u1ecdi $M$ l\u00e0 giao \u0111i\u1ec3m c\u1ee7a $OI$ v\u00e0 $AD, N$ l\u00e0 giao \u0111i\u1ec3m c\u1ee7a $O'I$ v\u00e0 $AE$.<br\/><b>C\u00e2u 3:<\/b> Cho $OA = 5cm,\\,O'A=3,2cm$. T\u00ednh \u0111\u1ed9 d\u00e0i c\u1ea1nh $DE$.<br\/><br\/><b>\u0110\u00e1p \u00e1n:<\/b> $DE=$_input_ $(cm)$<\/span>","explain":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D6.1.png' \/><\/center><span class='basic_left'> Ta c\u00f3: $ID=IA$; $IA=IE$ (t\u00ednh ch\u1ea5t hai ti\u1ebfp tuy\u1ebfn c\u1eaft nhau) <br\/> $\\Rightarrow IA=IE=ID$<br\/> $\\Delta OIO'$ vu\u00f4ng t\u1ea1i $I;AI\\bot OO'$ <br\/> $\\Rightarrow AI^2=OA.O'A$ (h\u1ec7 th\u1ee9c l\u01b0\u1ee3ng trong tam gi\u00e1c vu\u00f4ng) <br\/> $\\Rightarrow AI^2=5.3,2=16$ <br\/> $\\Rightarrow IA = 4\\, (cm)$ <br\/> $DE=2IA=$$2.4=8\\,(cm)$ <br\/> <span class='basic_pink'>V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u00e0 $8.$<\/span><\/span>"}]}],"id_ques":1225},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"\u0110\u1ec1 chung cho hai c\u00e2u","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"<span class='basic_left'>Cho \u0111\u01b0\u1eddng tr\u00f2n $(O)$, b\u00e1n k\u00ednh $OB$ v\u00e0 \u0111\u01b0\u1eddng tr\u00f2n \u0111\u01b0\u1eddng k\u00ednh $OB$.<br\/><b>C\u00e2u 1:<\/b> V\u1ecb tr\u00ed t\u01b0\u01a1ng \u0111\u1ed1i c\u1ee7a hai \u0111\u01b0\u1eddng tr\u00f2n l\u00e0: <\/span>","select":["A. C\u1eaft nhau ","B. Ti\u1ebfp x\u00fac trong","C. Ti\u1ebfp x\u00fac ngo\u00e0i"],"explain":"<span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D7.png' \/><\/center> G\u1ecdi $O'$ l\u00e0 t\u00e2m \u0111\u01b0\u1eddng tr\u00f2n \u0111\u01b0\u1eddng k\u00ednh $OB$ <br\/> $OO'=OB-O'B$ <br\/> V\u1eady $(O)$ ti\u1ebfp x\u00fac trong v\u1edbi $(O')$ <br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 B. <\/span><\/span>","column":3}]}],"id_ques":1226},{"time":24,"part":[{"title":"\u0110i\u1ec1n d\u1ea5u (>;<;=) th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"\u0110\u1ec1 chung cho hai c\u00e2u","temp":"fill_the_blank","correct":[[["="]]],"list":[{"point":5,"width":40,"content":"","type_input":"","ques":"<span class='basic_left'>Cho \u0111\u01b0\u1eddng tr\u00f2n $(O)$, b\u00e1n k\u00ednh $OB$ v\u00e0 \u0111\u01b0\u1eddng tr\u00f2n \u0111\u01b0\u1eddng k\u00ednh $OB$.<br\/><b>C\u00e2u 2:<\/b> D\u00e2y $BD$ c\u1ee7a \u0111\u01b0\u1eddng tr\u00f2n l\u1edbn c\u1eaft \u0111\u01b0\u1eddng tr\u00f2n nh\u1ecf \u1edf $C$. So s\u00e1nh \u0111\u1ed9 d\u00e0i \u0111o\u1ea1n th\u1eb3ng $BC$ v\u00e0 $CD$. <br\/> <b>\u0110\u00e1p \u00e1n:<\/b> $BC$ _input_ $CD$<\/span>","explain":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D7.1.png' \/><\/center><span class='basic_left'> X\u00e9t $\\Delta OBC$ c\u00f3 $ O'B = O' C = O O'$ <br\/> $\\Rightarrow\\widehat{OCB}=90^o$ (t\u00ednh ch\u1ea5t trung tuy\u1ebfn trong tam gi\u00e1c vu\u00f4ng) <br\/> $\\Rightarrow OC\\bot BD$ <br\/> $\\Rightarrow BC = CD$ (\u0111\u1ecbnh l\u00ed \u0111\u01b0\u1eddng k\u00ednh v\u00e0 d\u00e2y cung)<br\/> <span class='basic_pink'>V\u1eady d\u1ea5u c\u1ea7n \u0111i\u1ec1n l\u00e0 d\u1ea5u = <\/span><\/span>"}]}],"id_ques":1227},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"<span class='basic_left'>Cho hai \u0111\u01b0\u1eddng tr\u00f2n $(O;8cm)$ v\u00e0 $(O';6cm)$ c\u1eaft nhau t\u1ea1i $A$ v\u00e0 $B$. \u0110o\u1ea1n n\u1ed1i t\u00e2m $OO' = 10cm$. Khi \u0111\u00f3 \u0111\u1ed9 d\u00e0i d\u00e2y chung $AB$ l\u00e0:<\/span>","select":["A. $\\dfrac{6}{5} \\, cm$ ","B. $\\dfrac{12}{5} \\, cm$","C. $\\dfrac{24}{5} \\, cm$","D. $\\dfrac{48}{5} \\, cm$"],"explain":"<span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D4.png' \/><\/center> G\u1ecdi $H$ l\u00e0 giao \u0111i\u1ec3m c\u1ee7a $AB$ v\u00e0 $OO'$<br\/> Ta c\u00f3: $OO'$ l\u00e0 trung tr\u1ef1c c\u1ee7a $AB$ (t\u00ednh ch\u1ea5t \u0111\u01b0\u1eddng n\u1ed1i t\u00e2m) <br\/> $O{{A}^{2}}+O'{{A}^{2}} = 8^2 + 6^2 $$= 100 = 10^2$$=OO{{'}^{2}}$ <br\/> $\\Rightarrow \\Delta OAO'$ vu\u00f4ng t\u1ea1i $A$ (\u0111\u1ecbnh l\u00ed Pitago \u0111\u1ea3o) <br\/>X\u00e9t $\\Delta OAO'$ vu\u00f4ng t\u1ea1i $ A; AH\\bot OO'$ <br\/> $\\Rightarrow AH.OO'=AO.AO'$ (h\u1ec7 th\u1ee9c l\u01b0\u1ee3ng trong tam gi\u00e1c vu\u00f4ng) <br\/> $\\Rightarrow AH=\\dfrac{OA.AO'}{OO'}$$=\\dfrac{6.8}{10}$$=\\dfrac{24}{5} (cm)$ <br\/> $AB=2AH$$=\\dfrac{48}{5}$ (cm) <br\/><br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 D. <\/span><\/span>","column":4}]}],"id_ques":1228},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"<span class='basic_left'>Trong h\u1ec7 tr\u1ee5c t\u1ecda \u0111\u1ed9 $Oxy$, cho \u0111\u01b0\u1eddng tr\u00f2n t\u00e2m $A(3;-2)$ v\u00e0 b\u00e1n k\u00ednh b\u1eb1ng $5$ v\u00e0 \u0111\u01b0\u1eddng tr\u00f2n t\u00e2m $B(-2;-2)$ b\u00e1n k\u00ednh b\u1eb1ng $4$. H\u00e3y x\u00e1c \u0111\u1ecbnh v\u1ecb tr\u00ed t\u01b0\u01a1ng \u0111\u1ed1i c\u1ee7a hai \u0111\u01b0\u1eddng tr\u00f2n.<\/span>","select":["A.Hai \u0111\u01b0\u1eddng tr\u00f2n tr\u00f9ng nhau ","B. Hai \u0111\u01b0\u1eddng tr\u00f2n c\u1eaft nhau t\u1ea1i hai \u0111i\u1ec3m ph\u00e2n bi\u1ec7t","C. Hai \u0111\u01b0\u1eddng tr\u00f2n ti\u1ebfp x\u00fac nhau","D. Hai \u0111\u01b0\u1eddng tr\u00f2n kh\u00f4ng c\u1eaft nhau"],"hint":"L\u1ea5y hai \u0111i\u1ec3m $A$ v\u00e0 $B$ tr\u00ean h\u1ec7 tr\u1ee5c t\u1ecda \u0111\u1ed9 r\u1ed3i v\u1ebd hai \u0111\u01b0\u1eddng tr\u00f2n","explain":"<span class='basic_left'><center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D9.1.png' \/><\/center> D\u1ec5 th\u1ea5y hai \u0111\u01b0\u1eddng tr\u00f2n c\u1eaft nhau<br\/><br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 B. <\/span><\/span>","column":1}]}],"id_ques":1229},{"time":24,"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"<span class='basic_left'>Cho hai \u0111\u01b0\u1eddng tr\u00f2n $(I;3cm)$ v\u00e0 $(A;4cm)$ c\u1eaft nhau t\u1ea1i $M$ v\u00e0 $N$. \u0110o\u1ea1n n\u1ed1i t\u00e2m $AI = 5cm$. T\u00ednh \u0111\u1ed9 d\u00e0i d\u00e2y chung $MN$.<\/span>","select":["A.$\\dfrac{6}{5}\\,cm$ ","B. $\\dfrac{12}{5}\\,cm$","C. $\\dfrac{24}{5}\\,cm$","D. $\\dfrac{48}{5}\\,cm$"],"explain":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/hinhhoc/bai10/lv1/img\/h925_D13.png' \/><\/center><span class='basic_left'> G\u1ecdi $H$ l\u00e0 giao \u0111i\u1ec3m c\u1ee7a $MN$ v\u00e0 $AI$ <br\/> Ta c\u00f3: $AI$ l\u00e0 trung tr\u1ef1c c\u1ee7a $MN$ (t\u00ednh ch\u1ea5t \u0111\u01b0\u1eddng n\u1ed1i t\u00e2m) <br\/> $IM^2+AM^2 = 3^2+4^2 $$= 25 = 5^2$$=AI^2$ <br\/> $\\Rightarrow \\Delta IMA$ vu\u00f4ng t\u1ea1i $M$ (\u0111\u1ecbnh l\u00ed Pitago \u0111\u1ea3o) <br\/> X\u00e9t $\\Delta IAM$ vu\u00f4ng t\u1ea1i $M; MH\\bot AI$ <br\/> $\\Rightarrow MH.AI=IM.AM$ (h\u1ec7 th\u1ee9c l\u01b0\u1ee3ng trong tam gi\u00e1c vu\u00f4ng) <br\/> $\\Rightarrow MH=\\dfrac{IM.AM}{MH}$$=\\dfrac{3.4}{5}$$=\\dfrac{12}{5}(cm)$ <br\/> $MN=2MH$$=2.\\dfrac{12}{5}$$=\\dfrac{24}{5}(cm)$ <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 C. <\/span><\/span>","column":4}]}],"id_ques":1230}],"lesson":{"save":0,"level":1}}