H\u00ecnh h\u1ecdc - Ch\u01b0\u01a1ng 2 - \u00d4n t\u1eadp ch\u01b0\u01a1ng 2 - B\u00e0i t\u1eadp tr\u1eafc nghi\u1ec7m<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/lop12.edu.vn\/hinh-hoc-chuong-2-on-tap-chuong-2-bai-tap-trac-nghiem\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"H\u00ecnh h\u1ecdc - Ch\u01b0\u01a1ng 2 - \u00d4n t\u1eadp ch\u01b0\u01a1ng 2 - B\u00e0i t\u1eadp tr\u1eafc nghi\u1ec7m\" \/>\n<meta property=\"og:description\" content=\"B\u00e0i 1 (trang 63 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao): Trong c\u00e1c m\u1ec7nh \u0111\u1ec1 sau, m\u1ec7nh \u0111\u1ec1 n\u00e0o \u0111\u00fang? A. M\u1ecdi h\u00ecnh h\u1ed9p c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp. B. M\u1ecdi h\u00ecnh h\u1ed9p \u0111\u1ee9ng c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp C. 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Trong c\u00e1c m\u1ec7nh \u0111\u1ec1 sau, m\u1ec7nh \u0111\u1ec1 n\u00e0o \u0111\u00fang?<\/p>\n

A. M\u1ecdi h\u00ecnh h\u1ed9p c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp.<\/p>\n

B. M\u1ecdi h\u00ecnh h\u1ed9p \u0111\u1ee9ng c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp<\/p>\n

C. M\u1ecdi h\u00ecnh h\u1ed9p c\u00f3 m\u1ed9t m\u1eb7t b\u00ean vu\u00f4ng g\u00f3c v\u1edbi \u0111\u00e1y \u0111\u1ec1u c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp.<\/p>\n

D. M\u1ecdi h\u00ecnh h\u1ed9p ch\u1eef nh\u1eadt c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp.<\/p>\n

V\u00ec h\u00ecnh h\u1ed9p ch\u1eef nh\u1eadt c\u00f3 hai \u0111\u00e1y n\u1ed9i ti\u1ebfp \u0111\u01b0\u1eddng tr\u00f2n n\u00ean c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp. Ch\u1ecdn D<\/p>\n

Trong s\u1ed1 c\u00e1c h\u00ecnh h\u1ed9p n\u1ed9i ti\u1ebfp m\u1ed9t m\u1eb7t c\u1ea7u b\u00e1n k\u00ednh R th\u00ec:<\/p>\n

A. H\u00ecnh h\u1ed9p c\u00f3 \u0111\u00e1y l\u00e0 h\u00ecnh vu\u00f4ng c\u00f3 th\u1ec3 t\u00edch l\u1edbn nh\u1ea5t.<\/p>\n

B. H\u00ecnh l\u1eadp Ph\u01b0\u01a1ng c\u00f3 th\u1ec3 t\u00edch l\u1edbn nh\u1ea5t.<\/p>\n

C. H\u00ecnh h\u1ed9p c\u00f3 c\u00e1c k\u00edch th\u01b0\u1edbc t\u1ea1o th\u00e0nh c\u1ea5p s\u1ed1 c\u1ed9ng sai kh\u00e1c 0 c\u00f3 th\u1ec3 t\u00edch l\u1edbn nh\u1ea5t.<\/p>\n

D. H\u00ecnh h\u1ed9p c\u00f3 k\u00edch th\u01b0\u1edbc t\u1ea1o th\u00e0nh c\u1ea5p s\u1ed1 nh\u00e2n c\u1ed9ng b\u1ed9i kh\u00e1c 1 c\u00f3 th\u1ec3 t\u00edch l\u1edbn nh\u1ea5t.<\/p>\n

G\u1ecdi c\u00e1c c\u1ea1nh c\u1ee7a h\u00ecnh h\u1ed9p ch\u1eef nh\u1eadt l\u00e0 a, b, c<\/p>\n

Khi \u0111\u00f3 V = abc l\u1edbn nh\u00e1t khi v\u00e0 ch\u1ec9 kh\u00ed a = b = c.<\/p>\n

V\u1eady h\u00ecnh \u0111\u00f3 l\u00e0 h\u00ecnh l\u1eadp ph\u01b0\u01a1ng. Ch\u1ecdn B<\/p>\n

M\u1ed9t h\u00ecnh c\u1ea7u c\u00f3 th\u1ec3 t\u00edch 4\u03c0\/3 ngo\u1ea1i ti\u1ebfp m\u1ed9t h\u00ecnh l\u1eadp ph\u01b0\u01a1ng. Trong c\u00e1c s\u1ed1 sau \u0111\u00e2y, s\u1ed1 n\u00e0o l\u00e0 th\u1ec3 t\u00edch kh\u1ed1i l\u1eadp Ph\u01b0\u01a1ng?<\/p>\n

Trong c\u00e1c m\u1ec7nh \u0111\u1ec1 sau, m\u1ec7nh \u0111\u1ec1 n\u00e0o \u0111\u00fang?<\/p>\n

A. H\u00ecnh ch\u00f3p c\u00f3 \u0111\u00e1y l\u00e0 t\u1ee9 gi\u00e1c b\u1ea5t k\u00ec c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp.<\/p>\n

B. H\u00ecnh ch\u00f3p c\u00f3 \u0111\u00e1y l\u00e0 h\u00ecnh thang vu\u00f4ng c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp.<\/p>\n

C. H\u00ecnh ch\u00f3p c\u00f3 \u0111\u00e1y l\u00e0 h\u00ecnh b\u00ecnh h\u00e0nh c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i c\u1ea7u.<\/p>\n

D. H\u00ecnh ch\u00f3p c\u00f3 \u0111\u00e1y l\u00e0 h\u00ecnh thang c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp.<\/p>\n

H\u00ecnh ch\u00f3p \u0111\u00e1y l\u00e0 h\u00ecnh thang c\u00e2n c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp. v\u00ec \u0111\u00e1y c\u00f3 \u0111\u01b0\u1eddng tr\u00f2n ngo\u1ea1i ti\u1ebfp n\u00ean c\u00e1c \u0111i\u1ec3m n\u1eb1m tr\u00ean tr\u1ee5c \u0111\u01b0\u1eddng tr\u00f2n \u0111\u1ec1u c\u00e1ch c\u00e1c \u0111\u1ec9nh \u1edf \u0111\u00e1y. M\u1eb7t ph\u1eb3ng trung tr\u1ef1c c\u1ee7a m\u1ed9t c\u1ea1nh b\u00ean c\u1eaft tr\u1ee5c \u0111\u01b0\u1eddng tr\u00f2n t\u1ea1i O th\u00ec O l\u00e0 t\u00e2m m\u1eb7t c\u1ea7u. Ch\u1ecdn D<\/p>\n

Cho t\u1ee9 di\u1ec7n \u0111\u1ec1u ABCD c\u00f3 d\u1ea1ng b\u1eb1ng a. t\u1eadp h\u1ee3p c\u00e1c \u0111i\u1ec3m M trong kh\u00f4ng gian sao cho MA^{2<\/sup>+MB^{2<\/sup>+MC^{2<\/sup>+MD^{2<\/sup>=2a^{2<\/sup>l\u00e0<\/p>\n}}}}}

a) M\u1eb7t c\u1ea7u c\u00f3 t\u00e2m l\u00e0 tr\u1ecdng t\u00e2m c\u1ee7a tam gi\u00e1c ABC v\u00e0 b\u00e1n k\u00ednh b\u1eb1ng a\u221a2\/2;<\/p>\n

b) M\u1eb7t c\u1ea7u c\u00f3 t\u00e2m l\u00e0 tr\u1ecdng t\u00e2m c\u1ee7a t\u1ee9 di\u1ec7n v\u00e0 b\u00e1n k\u00ednh b\u1eb1ng a\u221a2\/4<\/p>\n

c) M\u1eb7t c\u1ea7u c\u00f3 t\u00e2m l\u00e0 tr\u1ecdng t\u00e2m c\u1ee7a t\u1ee9 di\u1ec7n v\u00e0 b\u00e1n k\u00ednh b\u1eb1ng a\u221a2\/2<\/p>\n

d) \u0110\u01b0\u1eddng tr\u00f2n v\u1edbi t\u00e2m l\u00e0 tr\u1ecdng t\u00e2m tam gi\u00e1c ABC v\u00e0 b\u00e1n k\u00ednh b\u1eb1ng a\u221a2\/4<\/p>\n

G\u1ecdi G l\u00e0 tr\u1ecdng t\u00e2m c\u1ee7a kh\u1ed1i t\u1ee9 di\u1ec7n ABCD<\/p>\n

=> MA^{2<\/sup>+MB^{2<\/sup>+MC^{2<\/sup>+MD^{2<\/sup>=4MG^{2<\/sup>+GA^{2<\/sup>+GB^{2<\/sup>+GC^{2<\/sup>+MD^{2<\/sup>=4MG^{2<\/sup>+3a^{2<\/sup>\/2 =2a^{2<\/sup><\/p>\n}}}}}}}}}}}}

=> MG^{2<\/sup>=a^{2<\/sup>\/8 => M thu\u1ed9c m\u1eb7t c\u1ea7u t\u00e2m G, b\u00e1n k\u00ednh R = MG = a\u221a2\/4. Ch\u1ecdn B<\/p>\n}}

B\u00e1n k\u00ednh m\u1eb7t c\u1ea7u ti\u1ebfp x\u00fac v\u1edbi c\u00e1c c\u1ea1nh c\u1ee7a t\u1ee9 di\u1ec7n \u0111\u1ec1u ABCD c\u1ea1nh b\u1eb1ng a l\u00e0:<\/p>\n

Do t\u1ee9 di\u1ec7n ABCD l\u00e0 t\u1ee9 di\u1ec7n \u0111\u1ec1u n\u00ean t\u00e2m m\u1eb7t c\u1ea7u ti\u1ebfp x\u00fac c\u00e1c c\u1ea1nh tr\u00f9ng v\u1edbi t\u00e2m m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp n\u00ean R=a\u221a2\/2. Ch\u1ecdn A<\/p>\n

Trong c\u00e1c m\u1ec7nh \u0111\u1ec1 sau, m\u1ec7nh \u0111\u1ec1 n\u00e0o \u0111\u00fang?<\/p>\n

A. C\u00f3 duy nh\u1ea5t m\u1ed9t m\u1eb7t c\u1ea7u \u0111i qua hai \u0111\u01b0\u1eddng tr\u00f2n n\u1eb1m trong hai m\u1eb7t ph\u1eb3ng c\u1eaft nhau.<\/p>\n

B. C\u00f3 duy nh\u1ea5t m\u1ed9t m\u1eb7t c\u1ea7u \u0111i qua hai \u0111\u01b0\u1eddng tr\u00f2n n\u1eb1m trong hai m\u1eb7t ph\u1eb3ng song song.<\/p>\n

C. C\u00f3 duy nh\u1ea5t m\u1ed9t m\u1eb7t c\u1ea7u \u0111i qua hai \u0111\u01b0\u1eddng th\u1eb3ng c\u1eaft nhau n\u1eb1m trong hai m\u1eb7t ph\u1eb3ng ph\u00e2n bi\u1ec7t.<\/p>\n

Xem b\u00e0i 3a. ph\u1ea7n b\u00e0i t\u1eadp \u00f4n t\u1eadp ch\u01b0\u01a1ng II. Ch\u1ecdn D<\/p>\n

Cho hai \u0111i\u1ec3m A, B c\u1ed1 \u0111\u1ecbnh. T\u1eadp h\u1ee3p c\u00e1c \u0111i\u1ec3m M trong kh\u00f4ng gian sao cho di\u1ec7n t\u00edch tam gi\u00e1c MAB kh\u00f4ng \u0111\u1ed5i l\u00e0:<\/p>\n

G\u1ecdi kho\u1ea3ng c\u00e1ch t\u1eeb M \u0111\u1ebfn AB l\u00e0 d(M, AB)<\/p>\n

Suy ra M thu\u1ed9c m\u1eb7t tr\u1ee5 T tr\u1ee5c AB b\u00e1n k\u00ednh R = 2S\/AB. Ch\u1ecdn C<\/p>\n

Cho hai \u0111i\u1ec3m ph\u00e2n bi\u1ec7t A, B c\u1ed1 \u0111\u1ecbnh. M\u1ed9t \u0111\u01b0\u1eddng th\u1eb3ng l thay \u0111\u1ed5i lu\u00f4n \u0111i qua A v\u00e0 c\u00e1ch B m\u1ed9t kho\u1ea3ng AB\/2. G\u1ecdi H l\u00e0 h\u00ecnh chi\u1ebfu c\u1ee7a B tr\u00ean l. T\u1eadp h\u1ee3p \u0111i\u1ec3m H trong kh\u00f4ng gian l\u00e0:<\/p>\n

C. m\u1eb7t n\u00f3n \u00a0\u00a0\u00a0 D. \u0111\u01b0\u1eddng tr\u00f2n.<\/p>\n

V\u1eady t\u1eadp h\u1ee3p H thu\u1ed9c l l\u00e0 m\u1eb7t n\u00f3n H tr\u1ee5c AB, \u0111\u1ec9nh A, g\u00f3c \u1edf \u0111\u1ec9nh 60^{o<\/sup>. Ch\u1ecdn C<\/p>\n}

V\u1edbi \u0111i\u1ec3m O c\u1ed1 \u0111\u1ecbnh thu\u1ed9c m\u1eb7t ph\u1eb3ng (P) cho tr\u01b0\u1edbc, x\u00e9t \u0111\u01b0\u1eddng th\u1eb3ng l thay \u0111\u1ed5i \u0111i qua O v\u00e0 t\u1ea1o v\u1edbi (P) g\u00f3c 30^{o<\/sup>. T\u1eadp h\u1ee3p c\u00e1c \u0111\u01b0\u1eddng th\u1eb3ng l trong kh\u00f4ng gian l\u00e0:<\/p>\n}

A. m\u1eb7t ph\u1eb3ng\u00a0\u00a0\u00a0B. hai \u0111\u01b0\u1eddng th\u1eb3ng<\/p>\n

Qua O k\u1ebb \u0111\u01b0\u1eddng th\u1eb3ng \u0394 \u22a5 m\u1eb7t ph\u1eb3ng (P) th\u00ec g\u00f3c gi\u1eefa \u0394 v\u00e0 l \u03b2=90^{o<\/sup>-30^{o<\/sup>=\u301660^{o<\/sup><\/p>\n}}}

V\u1eady \u0111\u01b0\u1eddng th\u1eb3ng l lu\u00f4n t\u1ea1o v\u1edbi \u0394 m\u1ed9t g\u00f3c kh\u00f4ng \u0111\u1ed5i v\u00e0 \u0111i qua \u0111i\u1ec3m O c\u1ed1 \u0111\u1ecbnh tr\u00ean tg n\u00ean l thu\u1ed9c m\u1eb7t n\u00f3n H tr\u1ee5c \u0394 \u0111\u1ec9nh O v\u00e0 g\u00f3c \u1edf \u0111\u1ec9nh b\u1eb1ng = 120^{o<\/sup>. Ch\u1ecdn D<\/p>\n}

\n
\n
B\u00e0i 11 (trang 66 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
M\u1ed9t h\u00ecnh tr\u1ee5 c\u00f3 b\u00e1n k\u00ednh \u0111\u00e1y b\u1eb1ng a, \u0111\u01b0\u1eddng cao OO\u2019 = a \u221a3. M\u1ed9t \u0111o\u1ea1n th\u1eb3ng AB thay \u0111\u1ed5i sao cho g\u00f3c gi\u1eefa AB v\u00e0 tr\u1ee5c h\u00ecnh tr\u1ee5 b\u1eb1ng . M\u1ed9t \u0111o\u1ea1n th\u1eb3ng AB thay \u0111\u1ed5i sao cho g\u00f3c gi\u1eefa AB v\u00e0 tr\u1ee5c h\u00ecnh tr\u1ee5 b\u1eb1ng 30^{o<\/sup>, A, B thu\u1ed9c hai \u0111\u01b0\u1eddng tr\u00f2n \u0111\u00e1y c\u1ee7a h\u00ecnh tr\u1ee5, t\u1eadp h\u1ee3p trung \u0111i\u1ec3m I c\u1ee7a AB l\u00e0:<\/p>\n}
A. m\u1eb7t tr\u1ee5<\/p>\n
B. m\u1eb7t c\u1ea7u<\/p>\n
C. \u0111\u01b0\u1eddng tr\u00f2n c\u00f3 t\u00e2m l\u00e0 trung \u0111i\u1ec3m c\u1ee7a \u0111\u01b0\u1eddng cao h\u00ecnh tr\u1ee5 b\u00e1n k\u00ednh a\u221a3\/2 trong m\u1eb7t ph\u1eb3ng trung tr\u1ef1c c\u1ee7a OO\u2019.<\/p>\n
D. m\u1eb7t ph\u1eb3ng<\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
G\u1ecdi giao \u0111i\u1ec3m c\u1ee7a AB v\u1edbi OO\u2019 l\u00e0 H. Do g\u00f3c gi\u1eefa AB v\u00e0 OO\u2019 b\u1eb1ng \u301630\u3017^0. N\u00ean AB thay \u0111\u1ed5i th\u00ec I ch\u1ea1y tr\u00ean \u0111\u01b0\u1eddng tr\u00f2n t\u00e2m K l\u00e0 trung \u0111i\u1ec3m OO\u2019 b\u00e1n k\u00ednh R=a\u221a3\/2 trong m\u1eb7t ph\u1eb3ng trung tr\u1ef1c OO\u2019. Ch\u1ecdn C<\/p>\n
B\u00e0i 12 (trang 66 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Trong m\u1eb7t ph\u1eb3ng (P) cho g\u00f3c xOy. M\u1ed9t m\u1eb7t ph\u1eb3ng (Q) thay \u0111\u1ed5i v\u00e0 vu\u00f4ng g\u00f3c v\u1edbi \u0111\u01b0\u1eddng ph\u00e2n gi\u00e1c trong c\u1ee7a xOy, c\u1eaft Ox, Oy t\u1ea1i A, B. Trong (Q) l\u1ea5y \u0111i\u1ec3m M sao cho g\u00f3c AMB=90^{o<\/sup>. Khi \u1ea5y, \u0111i\u1ec3m M lu\u00f4n thu\u1ed9c:<\/p>\n}
A. \u0111\u01b0\u1eddng tr\u00f2n \u00a0\u00a0\u00a0 B. m\u1eb7t tr\u1ee5<\/p>\n
C. m\u1eb7t n\u00f3n \u00a0\u00a0\u00a0 D. m\u1eb7t c\u1ea7u<\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
G\u1ecdi Oz l\u00e0 tia ph\u00e2n gi\u00e1c c\u1ee7a g\u00f3c xOy, I l\u00e0 trung \u0111i\u1ec3m AB v\u00e0<\/p>\n
$\"\"$ <\/p>\n
Suy ra \u0394MOI=\u0394BOI.<\/p>\n
$\"\"$ <\/p>\n
V\u1eady M thu\u1ed9c m\u1eb7t n\u00f3n H tr\u1ee5c H tr\u1ee5c Oz, \u0111\u1ec9nh O g\u00f3c \u0111\u1ec9nh \u03b1. Ch\u1ecdn C<\/p>\n
B\u00e0i 13 (trang 66 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho h\u00ecnh l\u1eadp ph\u01b0\u01a1ng ABCD.A\u2019B\u2019C\u2019D\u2019 c\u00f3 c\u1ea1nh a. di\u1ec7n t\u00edch xung quanh c\u1ee7a h\u00ecnh n\u00f3n tr\u00f2n xoay sinh b\u1edfi \u0111\u01b0\u1eddng ch\u00e9o AC\u2019 khi quay quanh tr\u1ee5c AA\u2019 b\u1eb1ng.<\/p>\n
A. \u03c0a^{2<\/sup>\u221a6\u00a0\u00a0\u00a0 B. \u03c0a^{2<\/sup>\u221a3\u00a0\u00a0\u00a0C. \u03c0a^{2<\/sup>\u221a2\u00a0\u00a0\u00a0D. \u03c0a^{2<\/sup>\u221a5<\/p>\n}}}}
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
AC\u2019 l\u00e0 \u0111\u01b0\u1eddng sinh v\u00e0 AC\u2019 = a\u221a3, b\u00e1n k\u00ednh \u0111\u00e1y A\u2019C\u2019 =a\u221a2<\/p>\n
Di\u1ec7n t\u00edch xung quanh S_{zq<\/sub>=\u03c0Rl=\u03c0a\u221a2.a\u221a3=\u03c0a^{2<\/sup>\u221a6. ch\u1ecdn A<\/p>\n}}
B\u00e0i 14 (trang 66 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho h\u00ecnh n\u00f3n b\u00e1n k\u00ednh \u0111\u00e1y b\u1eb1ng a, m\u1ed9t d\u00e2y cung thay \u0111\u1ed5i c\u1ee7a \u0111\u01b0\u1eddng tr\u00f2n \u0111\u00e1y c\u00f3 \u0111\u1ed9 d\u00e0i kh\u00f4ng \u0111\u1ed5i b\u1eb1ng a. T\u1eadp h\u01a1p trung \u0111i\u1ec3m I c\u1ee7a d\u00e2y cung l\u00e0:<\/p>\n
A. M\u1eb7t n\u00f3n c\u1ed1 \u0111\u1ecbnh \u00a0\u00a0\u00a0B. M\u1eb7t ph\u1eb3ng c\u1ed1 \u0111\u1ecbnh<\/p>\n
C. M\u1eb7t tr\u1ee5 c\u1ed1 \u0111\u1ecbnh \u00a0\u00a0\u00a0D. \u0110\u01b0\u1eddng tr\u00f2n c\u1ed1 \u0111\u1ecbnh.<\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
G\u1ecdi d\u00e2y cung AB = a, I l\u00e0 trung \u0111i\u1ec3m c\u1ee7a AB. Do d\u00e2y cung c\u00f3 \u0111\u1ed9 d\u00e0i b\u1eb1ng a. Kh\u00f4ng \u0111\u1ed5i n\u00ean n\u00f3 chuy\u1ec3n \u0111\u1ed9ng tr\u00ean \u0111\u01b0\u1eddng tr\u00f2n \u0111\u00e1y th\u00ec trung \u0111i\u1ec3m I c\u0169ng ch\u1ea1y tr\u00ean \u0111\u01b0\u1eddng tr\u00f2n c\u00f3 b\u00e1n k\u00ednh a\u221a3\/2. Ch\u1ecdn D<\/p>\n
B\u00e0i 15 (trang 66 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho h\u00ecnh tr\u1ee5 c\u00f3 b\u00e1n k\u00ednh \u0111\u00e1y R, \u0111\u01b0\u1eddng cao OO\u2019. C\u1eaft h\u00ecnh tr\u1ee5 \u0111\u00f3 b\u1eb1ng m\u1eb7t ph\u1eb3ng (\u03b1) vu\u00f4ng g\u00f3c v\u1edbi \u0111\u00e1y v\u00e0 c\u00e1ch \u0111i\u1ec3m O m\u1ed9t kho\u1ea3ng c\u00e1ch h cho tr\u01b0\u1edbc (h < R). Khi \u1ea5y, mp (\u03b1) c\u00f3 t\u00ednh ch\u1ea5t:<\/p>\n
A. Lu\u00f4n ti\u1ebfp x\u00fac v\u1edbi m\u1ed9t m\u1eb7t tr\u1ee5 c\u1ed1 \u0111\u1ecbnh.<\/p>\n
B. Lu\u00f4n c\u00e1ch m\u1eb7t ph\u1eb3ng cho tr\u01b0\u1edbc qua tr\u1ee5c h\u00ecnh tr\u1ee5 m\u1ed9t kho\u1ea3ng h,<\/p>\n
C. C\u1eaft h\u00ecnh tr\u1ee5 theo thi\u1ebft di\u1ec7n h\u00ecnh vu\u00f4ng.<\/p>\n
D. C\u1ea3 ba t\u00ednh ch\u1ea5t tr\u00ean \u0111\u1ec1u sai.<\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
V\u00ec kho\u1ea3ng c\u00e1ch t\u1eeb O \u0111\u1ebfn (\u03b1) b\u1eb1ng h c\u1ed1 \u0111\u1ecbnh v\u00e0 \u03b1 \u22a5 \u0111\u00e1y n\u00ean (\u03b1) ti\u1ebfp x\u00fac v\u1edbi tr\u1ee5 tr\u1ee5c OO\u2019 b\u00e1n k\u00ednh h. ch\u1ecdn A<\/p>\n
B\u00e0i 16 (trang 67 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
M\u1ed9t kh\u1ed1i tr\u1ee5 b\u00e1n k\u00ednh \u0111\u00e1y a\u221a3, chi\u1ec1u cao 2a\u221a3. Th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i c\u1ea7u ngo\u1ea1i ti\u1ebfp kh\u1ed1i tr\u1ee5 l\u00e0:<\/p>\n
$\"\"$ <\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
<\/div>\n
B\u00e1n k\u00ednh m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp<\/p>\n
$\"\"$ <\/p>\n
Ch\u1ecdn A<\/p>\n
B\u00e0i 17 (trang 67 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho h\u00ecnh n\u00f3n c\u00f3 \u0111\u01b0\u1eddng sinh b\u1eb1ng \u0111\u01b0\u1eddng k\u00ednh \u0111\u00e1y b\u1eb1ng 2. B\u00e1n k\u00ednh m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp h\u00ecnh n\u00f3n \u0111\u00f3 l\u00e0:<\/p>\n
$\"\"$ <\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
Do \u0111\u01b0\u1eddng sinh b\u1eb1ng \u0111\u01b0\u1eddng k\u00ednh \u0111\u00e1y n\u00ean b\u00e1n k\u00ednh m\u1eb7t c\u1ea7u: R=2h\/3 , v\u1edbi h l\u00e0 \u0111\u01b0\u1eddng cao tam gi\u00e1c \u0111\u1ec1u c\u00f3 c\u1ea1nh b\u1eb1ng 2.<\/p>\n
$\"\"$ <\/p>\n
B\u00e0i 18 (trang 67 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho h\u00ecnh n\u00f3n sinh b\u1edfi m\u1ed9t tam gi\u00e1c \u0111\u1ec1u c\u1ea1nh a khi quay quanh m\u1ed9t \u0111\u01b0\u1eddng cao. M\u1ed9t m\u1eb7t c\u1ea7u c\u00f3 di\u1ec7n t\u00edch b\u1eb1ng di\u1ec7n t\u00edch to\u00e0n ph\u1ea7n c\u1ee7a h\u00ecnh n\u00f3n c\u00f3 b\u00e1n k\u00ednh l\u00e0:<\/p>\n
$\"\"$ <\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
Di\u1ec7n t\u00edch h\u00ecnh c\u1ea7u<\/p>\n
$\"\"$ <\/p>\n
Ch\u1ecdn A<\/p>\n
B\u00e0i 19 (trang 67 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho m\u1ed9t h\u00ecnh n\u00f3n sinh b\u1edfi m\u1ed9t tam gi\u00e1c \u0111\u1ec1u c\u1ea1nh a khi quay quanh m\u1ed9t \u0111\u01b0\u1eddng cao. M\u1ed9t kh\u1ed1i c\u1ea7u c\u00f3 th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i n\u00f3n th\u00ec c\u00f3 b\u00e1n k\u00ednh b\u1eb1ng<\/p>\n
$\"\"$ <\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
$\"\"$ <\/p>\n
Ch\u1ecdn A<\/p>\n
B\u00e0i 20 (trang 67 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho h\u00ecnh ch\u00f3p t\u1ee9 gi\u00e1c \u0111\u1ec1u c\u1ea1nh \u0111\u00e1y b\u1eb1ng a v\u00e0 g\u00f3c \u1edf \u0111\u1ec9nh b\u1eb1ng 90^{o<\/sup>. C\u1eaft h\u00ecnh n\u00f3n b\u1eb1ng m\u1eb7t ph\u1eb3ng (\u03b1) \u0111i qua \u0111\u1ec9nh sao cho g\u00f3c gi\u1eefa (\u03b1) v\u00e0 m\u1eb7t \u0111\u00e1y h\u00ecnh n\u00f3n b\u1eb1ng 60^{o<\/sup>. Khi \u0111\u00f3 di\u1ec7n t\u00edch thi\u1ebft di\u1ec7n l\u00e0:<\/p>\n}}
$\"\"$ <\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
Ch\u1ecdn A<\/p>\n
\n
\n
B\u00e0i 21 (trang 67 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho h\u00ecnh ch\u00f3p t\u1ee9 gi\u00e1c \u0111\u1ec1u c\u1ea1nh \u0111\u00e1y b\u1eb1ng a, c\u1ea1nh b\u00ean t\u1ea1o v\u1edbi m\u1eb7t \u0111\u00e1y g\u00f3c 60^{o<\/sup>. Di\u1ec7n t\u00edch to\u00e0n ph\u1ea7n c\u1ee7a h\u00ecnh n\u00f3n ngo\u1ea1i ti\u1ebfp h\u00ecnh ch\u00f3p l\u00e0:<\/p>\n}
$\"\"$ <\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
Ch\u1ecdn A<\/p>\n
B\u00e0i 22 (trang 68 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho m\u1eb7t c\u1ea7u b\u00e1n k\u00ednh R v\u00e0 m\u1ed9t h\u00ecnh tr\u1ee5 c\u00f3 b\u00e1n k\u00ednh \u0111\u00e1y R v\u00e0 chi\u1ec1u cao 2R. T\u1ec9 s\u1ed1 th\u1ec3 t\u00edch kh\u1ed1i c\u1ea7u v\u00e0 kh\u1ed1i tr\u1ee5 l\u00e0:<\/p>\n
$\"\"$ <\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
<\/div>\n
$\"\"$ <\/p>\n
B\u00e0i 23 (trang 68 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho h\u00ecnh tr\u1ee5 c\u00f3 b\u00e1n k\u00ednh \u0111\u00e1y R, chi\u1ec1u cao c\u0169ng b\u1eb1ng R. M\u1ed9t h\u00ecnh vu\u00f4ng ABCD c\u00f3 hai c\u1ea1nh AB v\u00e0 CD l\u1ea7n l\u01b0\u1ee3t l\u00e0 c\u00e1c d\u00e2y cung c\u1ee7a hai \u0111\u01b0\u1eddng tr\u00f2n \u0111\u00e1y, mp (ABCD) kh\u00f4ng vu\u00f4ng g\u00f3c v\u1edbi m\u1eb7t ph\u1eb3ng \u0111\u00e1y h\u00ecnh tr\u1ee5. Di\u1ec7n t\u00edch h\u00ecnh vu\u00f4ng \u0111\u00f3 l\u00e0:<\/p>\n
$\"\"$ <\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
$\"\"$ <\/p>\n
Ch\u1ecdn A<\/p>\n
B\u00e0i 24 (trang 68 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
M\u1ed9t kh\u1ed1i h\u1ed9p ch\u1eef nh\u1eadt n\u1ed9i ti\u1ebfp trong m\u1ed9t kh\u1ed1i tr\u1ee5, ba k\u00edch th\u01b0\u1edbc c\u1ee7a h\u00ecnh h\u1ed9p ch\u1eef nh\u1eadt a, b, c. th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i tr\u1ee5 l\u00e0:<\/p>\n
$\"\"$ <\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
N\u1ebfu \u0111\u01b0\u1eddng cao l\u00e0 c th\u00ec th\u1ec3 t\u00edch<\/p>\n
$\"\"$ <\/p>\n
N\u1ebfu \u0111\u01b0\u1eddng cao l\u00e0 b th\u00ec<\/p>\n
$\"\"$ <\/p>\n
N\u1ebfu \u0111\u01b0\u1eddng cao l\u00e0 a th\u00ec<\/p>\n
$\"\"$ <\/p>\n
B\u00e0i 25 (trang 68 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
M\u1ed9t kh\u1ed1i t\u1ee9 di\u1ec7n \u0111\u1ec1u c\u00f3 c\u1ea1nh a n\u1ed9i ti\u1ebfp kh\u1ed1i n\u00f3n. Th\u1ec3 t\u00edch kh\u1ed1i n\u00f3n l\u00e0:<\/p>\n
$\"\"$ <\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
<\/div>\n
Kh\u1ed1i n\u00f3n c\u00f3 \u0111\u01b0\u1eddng cao h b\u1eb1ng \u0111\u01b0\u1eddng cao c\u1ee7a t\u1ee9 di\u1ec7n h\u1ea1 t\u1eeb m\u1ed9t \u0111\u1ec9nh \u0111\u1ebfn m\u1ed9t \u0111\u1ed1i di\u1ec7n h = a \u221a6\/3<\/p>\n
B\u00e1n k\u00ednh \u0111\u00e1y b\u1eb1ng 2\/3 \u0111\u01b0\u1eddng cao tam gi\u00e1c \u0111\u1ec1u,<\/p>\n
$\"\"$ <\/p>\n
Ch\u1ecdn B<\/p>\n
B\u00e0i 26 (trang 68 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao):<\/b><\/p>\n
Cho h\u00ecnh n\u00f3n \u0111\u1ec9nh S, \u0111\u00e1y l\u00e0 h\u00ecnh tr\u00f2n t\u00e2m O, g\u00f3c \u1edf \u0111\u1ec9nh b\u1eb1ng 120^{o<\/sup>. Tr\u00ean \u0111\u01b0\u1eddng tr\u00f2n \u0111\u00e1y, l\u1ea5y \u0111i\u1ec3m A c\u1ed1 \u0111\u1ecbnh v\u00e0 \u0111i\u1ec3m M di \u0111\u1ed9ng. G\u1ecdi a l\u00e0 di\u1ec7n t\u00edch c\u1ee7a tam gi\u00e1c SAM. C\u00f3 bao nhi\u00eau v\u1ecb tr\u00ed c\u1ee7a M \u0111\u1ec3 s \u0111\u1ea1t gi\u00e1 tr\u1ecb l\u1edbn nh\u1ea5t?<\/p>\n}
A. c\u00f3 1 v\u1ecb tr\u00ed \u00a0\u00a0\u00a0B. c\u00f3 2 v\u1ecb tr\u00ed<\/p>\n
C. c\u00f3 3 v\u1ecb tr\u1ecb \u00a0\u00a0\u00a0 D. c\u00f3 v\u00f4 s\u1ed1 v\u1ecb tr\u00ed<\/p>\n
L\u1eddi gi\u1ea3i:<\/b><\/p>\n
G\u1ecdi A\u2019 \u0111\u1ed1i x\u1ee9ng v\u1edbi A qua t\u00e2m O c\u1ee7a \u0111\u01b0\u1eddng tr\u00f2n \u0111\u00e1y<\/p>\n
$\"\"$ <\/p>\n
V\u1eady di\u1ec7n t\u00edch nh\u1ecf nh\u1ea5t khi SA \u22a5SM => M n\u1eb1m tr\u00ean 2 n\u1eeda \u0111\u01b0\u1eddng tr\u00f2n (O) sao cho SA \u22a5SM. V\u00e0 c\u00f3 2 \u0111i\u1ec3m M nh\u01b0 v\u1eady. Ch\u1ecdn B<\/p>\n
\n
<\/div>\n<\/div>\n
Ch\u1ecdn D<\/p>\n
\n
<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"
B\u00e0i 1 (trang 63 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao): Trong c\u00e1c m\u1ec7nh \u0111\u1ec1 sau, m\u1ec7nh \u0111\u1ec1 n\u00e0o \u0111\u00fang? A. M\u1ecdi h\u00ecnh h\u1ed9p c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp. B. M\u1ecdi h\u00ecnh h\u1ed9p \u0111\u1ee9ng c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i ti\u1ebfp C. M\u1ecdi h\u00ecnh h\u1ed9p c\u00f3 m\u1ed9t m\u1eb7t b\u00ean vu\u00f4ng g\u00f3c v\u1edbi \u0111\u00e1y \u0111\u1ec1u c\u00f3 m\u1eb7t c\u1ea7u ngo\u1ea1i […]<\/p>\n","protected":false},"author":3,"featured_media":22226,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"tdm_status":"","tdm_grid_status":""},"categories":[1302],"tags":[1392,1393],"yoast_head":"\nH\u00ecnh h\u1ecdc - Ch\u01b0\u01a1ng 2 - \u00d4n t\u1eadp ch\u01b0\u01a1ng 2 - B\u00e0i t\u1eadp tr\u1eafc nghi\u1ec7m<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/lop12.edu.vn\/hinh-hoc-chuong-2-on-tap-chuong-2-bai-tap-trac-nghiem\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"H\u00ecnh h\u1ecdc - Ch\u01b0\u01a1ng 2 - \u00d4n t\u1eadp ch\u01b0\u01a1ng 2 - B\u00e0i t\u1eadp tr\u1eafc nghi\u1ec7m\" \/>\n<meta property=\"og:description\" content=\"B\u00e0i 1 (trang 63 sgk H\u00ecnh H\u1ecdc 12 n\u00e2ng cao): Trong c\u00e1c m\u1ec7nh \u0111\u1ec1 sau, m\u1ec7nh \u0111\u1ec1 n\u00e0o \u0111\u00fang? 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