C\u00e2u 7:<\/b>\u00a0\u0110\u1ec3 l\u00e0m m\u1ed9t th\u00f9ng phi h\u00ecnh tr\u1ee5 ng\u01b0\u1eddi ta c\u1ea7n hai mi\u1ebfng nh\u1ef1a h\u00ecnh tr\u00f2n l\u00e0m hai \u0111\u00e1y c\u00f3 di\u1ec7n t\u00edch m\u1ed7i h\u00ecnh l\u00e0 4\u03c0(cm2<\/sup>) v\u00e0 m\u1ed9t mi\u1ebfng nh\u1ef1a h\u00ecnh ch\u1eef nh\u1eadt c\u00f3 di\u1ec7n t\u00edch l\u00e0 15\u03c0(cm2<\/sup>) \u0111\u1ec3 l\u00e0m th\u00e2n. T\u00ednh chi\u1ec1u cao c\u1ee7a th\u00f9ng phi \u0111\u01b0\u1ee3c l\u00e0m.<\/p>\n A. 15\/4(cm)\u00a0\u00a0\u00a0B. 5(cm)\u00a0\u00a0\u00a0C. 15\/2(cm)\u00a0\u00a0\u00a0D. 15(cm)<\/p>\n C\u00e2u 8:<\/b>\u00a0Cho h\u00ecnh ch\u1eef nh\u1eadt ABCD c\u00f3 AB = 2AD. L\u1ea7n l\u01b0\u1ee3t quay h\u00ecnh ch\u1eef nh\u1eadt quanh c\u00e1c tr\u1ee5c AB, AD ta \u0111\u01b0\u1ee3c hai kh\u1ed1i tr\u1ee5 l\u1ea7n l\u01b0\u1ee3t g\u1ecdi l\u00e0 (H1), (H2). T\u00ednh t\u1ec9 s\u1ed1 th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i tr\u1ee5 (H1) chia cho th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i tr\u1ee5 (H2)<\/p>\n A. 1\u00a0\u00a0\u00a0B. 1\/4 \u00a0\u00a0\u00a0C. 1\/2 \u00a0\u00a0\u00a0D. 2<\/p>\n C\u00e2u 9:<\/b>\u00a0Cho h\u00ecnh tr\u1ee5 c\u00f3 b\u00e1n k\u00ednh \u0111\u00e1y b\u1eb1ng a v\u00e0 di\u1ec7n t\u00edch to\u00e0n ph\u1ea7n 6\u03c0a2<\/sup>. Di\u1ec7n t\u00edch c\u1ee7a thi\u1ebft di\u1ec7n c\u1ee7a h\u00ecnh tr\u1ee5 c\u1eaft b\u1edfi m\u1eb7t ph\u1eb3ng (P) \u0111i qua c\u00e1c tr\u1ee5c c\u1ee7a h\u00ecnh tr\u1ee5 l\u00e0 :<\/p>\n A. a2<\/sup>\u00a0\u00a0\u00a0B. 2a2<\/sup>\u00a0\u00a0\u00a0C. 4a2<\/sup>\u00a0\u00a0\u00a0D. 6a2<\/sup><\/p>\n C\u00e2u 10:<\/b>\u00a0Cho kh\u1ed1i tr\u1ee5 c\u00f3 di\u1ec7n t\u00edch to\u00e0n ph\u1ea7n l\u00e0 \u03c0 v\u00e0 c\u00f3 thi\u1ebft di\u1ec7n c\u1eaft b\u1edfi m\u1eb7t ph\u1eb3ng \u0111i qua tr\u1ee5c l\u00e0 h\u00ecnh vu\u00f4ng. Th\u1ec3 t\u00edch kh\u1ed1i tr\u1ee5 l\u00e0 :<\/p>\n <\/p>\n C\u00e2u 11:<\/b>\u00a0Cho h\u00ecnh n\u00f3n \u0111\u1ec9nh I v\u00e0 \u0111\u01b0\u1eddng tr\u00f2n \u0111\u00e1y t\u00e2m O. B\u00e1n k\u00ednh \u0111\u00e1y b\u1eb1ng chi\u1ec1u cao c\u1ee7a h\u00ecnh n\u00f3n b\u1eb1ng a. Hai \u0111i\u1ec3m A, B n\u1eb1m tr\u00ean \u0111\u01b0\u1eddng tr\u00f2n t\u00e2m O sao cho AB = a\/2 . Th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i t\u1ee9 di\u1ec7n IABO l\u00e0 :<\/p>\n <\/p>\n C\u00e2u 12:<\/b>\u00a0Cho h\u00ecnh n\u00f3n c\u00f3 \u0111\u01b0\u1eddng cao v\u00e0 b\u00e1n k\u00ednh \u0111\u00e1y b\u1eb1ng nhau v\u00e0 b\u1eb1ng R. Trong t\u1ea5t c\u1ea3 c\u00e1c kh\u1ed1i tr\u1ee5 n\u1eb1m trong h\u00ecnh n\u00f3n c\u00f3 m\u1ed9t \u0111\u00e1y thu\u1ed9c m\u1eb7t \u0111\u00e1y c\u1ee7a h\u00ecnh n\u00f3n v\u00e0 \u0111\u01b0\u1eddng tr\u00f2n \u0111\u00e1y c\u00f2n l\u1ea1i thu\u1ed9c h\u00ecnh n\u00f3n, th\u1ec3 t\u00edch kh\u1ed1i tr\u1ee5 l\u1edbn nh\u1ea5t l\u00e0 :<\/p>\n <\/p>\n H\u01b0\u1edbng d\u1eabn gi\u1ea3i v\u00e0 \u0110\u00e1p \u00e1n<\/b><\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" C\u00e2u 7:\u00a0\u0110\u1ec3 l\u00e0m m\u1ed9t th\u00f9ng phi h\u00ecnh tr\u1ee5 ng\u01b0\u1eddi ta c\u1ea7n hai mi\u1ebfng nh\u1ef1a h\u00ecnh tr\u00f2n l\u00e0m hai \u0111\u00e1y c\u00f3 di\u1ec7n t\u00edch m\u1ed7i h\u00ecnh l\u00e0 4\u03c0(cm2) v\u00e0 m\u1ed9t mi\u1ebfng nh\u1ef1a h\u00ecnh ch\u1eef nh\u1eadt c\u00f3 di\u1ec7n t\u00edch l\u00e0 15\u03c0(cm2) \u0111\u1ec3 l\u00e0m th\u00e2n. T\u00ednh chi\u1ec1u cao c\u1ee7a th\u00f9ng phi \u0111\u01b0\u1ee3c l\u00e0m. A. 15\/4(cm)\u00a0\u00a0\u00a0B. 5(cm)\u00a0\u00a0\u00a0C. 15\/2(cm)\u00a0\u00a0\u00a0D. 15(cm) C\u00e2u […]<\/p>\n","protected":false},"author":3,"featured_media":28764,"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 7-A<\/td>\n 8-C<\/td>\n 9-C<\/td>\n 10-D<\/td>\n 11-B<\/td>\n 12-C<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n