C\u00e2u 8:<\/b>\u00a0T\u00ednh th\u1ec3 t\u00edch V c\u1ee7a h\u00ecnh ch\u00f3p S.ABC c\u00f3 \u0111\u00e1y l\u00e0 tam gi\u00e1c vu\u00f4ng t\u1ea1i A, SAB l\u00e0 tam gi\u00e1c \u0111\u1ec1u c\u1ea1nh a, m\u1eb7t (SAB) vu\u00f4ng g\u00f3c v\u1edbi \u0111\u00e1y, BC = a\u221a3<\/p>\n
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C\u00e2u 9:<\/b>\u00a0Cho h\u00ecnh ch\u00f3p S.ABCD c\u00f3 \u0111\u00e1y l\u00e0 h\u00ecnh b\u00ecnh h\u00e0nh. G\u1ecdi M l\u00e0 trung \u0111i\u1ec3m c\u1ee7a SC, m\u1eb7t ph\u1eb3ng qua AM v\u00e0 song song v\u1edbi BD c\u1eaft SB, SD l\u1ea7n l\u01b0\u1ee3t t\u1ea1i E, F. T\u00ednh t\u1ec9 s\u1ed1 k gi\u1eefa th\u1ec3 t\u00edch h\u00ecnh ch\u00f3p S.AEMF v\u00e0 th\u1ec3 t\u00edch h\u00ecnh ch\u00f3p S.ABCD.<\/p>\n
A. k = 1\/3\u00a0\u00a0\u00a0B. k = 1\/4\u00a0\u00a0\u00a0C. k = 1\/6\u00a0\u00a0\u00a0D. k = 1\/9<\/p>\n
C\u00e2u 10:<\/b>\u00a0Cho h\u00ecnh ch\u00f3p S.ABC. L\u1ea5y c\u00e1c \u0111i\u1ec3m A’, B’, C’ sao cho<\/p>\n
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G\u1ecdi V l\u00e0 th\u1ec3 t\u00edch h\u00ecnh ch\u00f3p S.ABC, V\u2019 l\u00e0 th\u1ec3 t\u00edch h\u00ecnh ch\u00f3p S.A\u2019B\u2019C\u2019.<\/p>\n
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C\u00e2u 11:<\/b>\u00a0Cho h\u00ecnh ch\u00f3p S.ABC c\u00f3 \u0111\u00e1y l\u00e0 tam gi\u00e1c vu\u00f4ng c\u00e2n \u1edf B, AB = a, SA = a\u221a2 v\u00e0 SA vu\u00f4ng g\u00f3c v\u1edbi \u0111\u00e1y. G\u1ecdi M, N l\u1ea7n l\u01b0\u1ee3t l\u00e0 ch\u00e2n \u0111\u01b0\u1eddng cao h\u1ea1 t\u1eeb A \u0111\u1ebfn SB v\u00e0 SC. T\u00ednh t\u1ec9 s\u1ed1 k gi\u1eefa th\u1ec3 t\u00edch h\u00ecnh ch\u00f3p S.ANM v\u00e0 th\u1ec3 t\u00edch h\u00ecnh ch\u00f3p S.ABC<\/p>\n
A. k = 1\/6\u00a0\u00a0\u00a0B. k = 1\/4\u00a0\u00a0\u00a0C. k = 1\/3 \u00a0\u00a0\u00a0D. k = 1\/2<\/p>\n
C\u00e2u 12:<\/b>\u00a0Cho h\u00ecnh ch\u00f3p S.ABC c\u00f3 \u0111\u00e1y l\u00e0 tam gi\u00e1c vu\u00f4ng c\u00e2n \u1edf B, AB = a, SA = a\u221a2 v\u00e0 SA vu\u00f4ng g\u00f3c v\u1edbi \u0111\u00e1y. G\u1ecdi M, N l\u1ea7n l\u01b0\u1ee3t l\u00e0 ch\u00e2n \u0111\u01b0\u1eddng cao h\u1ea1 t\u1eeb A \u0111\u1ebfn SB v\u00e0 SC. T\u00ednh th\u1ec3 t\u00edch V c\u1ee7a h\u00ecnh ch\u00f3p S.ANM<\/p>\n
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C\u00e2u 13:<\/b>\u00a0T\u00ednh th\u1ec3 t\u00edch h\u00ecnh ch\u00f3p S.ABCD c\u00f3 \u0111\u00e1y l\u00e0 h\u00ecnh ch\u1eef nh\u1eadt, m\u1eb7t SAB l\u00e0 tam gi\u00e1c \u0111\u1ec1u, h\u00ecnh chi\u1ebfu c\u1ee7a S l\u00ean \u0111\u00e1y tr\u00f9ng v\u1edbi trung \u0111i\u1ec3m c\u1ee7a AC, AC = 2a, AB = \u221a3a<\/p>\n
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C\u00e2u 14:<\/b>\u00a0Cho h\u00ecnh ch\u00f3p S.ABC c\u00f3 SC vu\u00f4ng g\u00f3c v\u1edbi \u0111\u00e1y, AB = a, AC = 2a, SC = BC = a\u221a5. M\u1eb7t ph\u1eb3ng (P) qua C vu\u00f4ng g\u00f3c v\u1edbi SB c\u1eaft SA, SB l\u1ea7n l\u01b0\u1ee3t t\u1ea1i A\u2019, B\u2019. T\u00ednh t\u1ec9 s\u1ed1 k gi\u1eefa th\u1ec3 t\u00edch h\u00ecnh ch\u00f3p S.A\u2019B\u2019C\u2019 v\u00e0 th\u1ec3 t\u00edch h\u00ecnh ch\u00f3p S.ABC.<\/p>\n
A. k = 5\/18\u00a0\u00a0\u00a0B. k = 1\/3\u00a0\u00a0\u00a0C. k = 7\/18\u00a0\u00a0\u00a0D. k = 4\/9<\/p>\n
H\u01b0\u1edbng d\u1eabn gi\u1ea3i v\u00e0 \u0110\u00e1p \u00e1n<\/b><\/p>\n C\u00e2u 11:<\/b><\/p>\n Ta c\u00f3: SN = SA\u221a2\/2 = a, SB = a\u221a3<\/p>\n D\u1ec5 th\u1ea5y CB \u22a5 SB, AM \u22a5 (SBC) suy ra SC \u22a5 (ANM), do \u0111\u00f3:<\/p>\n <\/p>\n C\u00e2u 12:<\/b><\/p>\n Ta c\u00f3:<\/p>\n <\/p>\n \u00c1p d\u1ee5ng b\u00e0i tr\u00ean ta c\u00f3:<\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" C\u00e2u 8:\u00a0T\u00ednh th\u1ec3 t\u00edch V c\u1ee7a h\u00ecnh ch\u00f3p S.ABC c\u00f3 \u0111\u00e1y l\u00e0 tam gi\u00e1c vu\u00f4ng t\u1ea1i A, SAB l\u00e0 tam gi\u00e1c \u0111\u1ec1u c\u1ea1nh a, m\u1eb7t (SAB) vu\u00f4ng g\u00f3c v\u1edbi \u0111\u00e1y, BC = a\u221a3 C\u00e2u 9:\u00a0Cho h\u00ecnh ch\u00f3p S.ABCD c\u00f3 \u0111\u00e1y l\u00e0 h\u00ecnh b\u00ecnh h\u00e0nh. G\u1ecdi M l\u00e0 trung \u0111i\u1ec3m c\u1ee7a SC, m\u1eb7t ph\u1eb3ng qua AM […]<\/p>\n","protected":false},"author":3,"featured_media":28819,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"tdm_status":"","tdm_grid_status":""},"categories":[157],"tags":[1450,1448],"yoast_head":"\n\n\n
\n 8-B<\/td>\n 9-A<\/td>\n 10-A<\/td>\n 11-C<\/td>\n 12-B<\/td>\n 13-A<\/td>\n 14-A<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n