C\u00e2u 1:<\/b>\u00a0Kh\u1ed1i 20 m\u1eb7t \u0111\u1ec1u c\u00f3 bao nhi\u00eau c\u1ea1nh?<\/p>\n
A. 24 c\u1ea1nh \u00a0\u00a0\u00a0B. 28 c\u1ea1nh\u00a0\u00a0\u00a0C. 30 c\u1ea1nh\u00a0\u00a0\u00a0D. 40 c\u1ea1nh<\/p>\n
C\u00e2u 2:<\/b>\u00a0Kh\u1ed1i 12 m\u1eb7t \u0111\u1ec1u c\u00f3 bao nhi\u00eau \u0111\u1ec9nh ?<\/p>\n
A. 10 \u0111\u1ec9nh\u00a0\u00a0\u00a0B. 12 \u0111\u1ec9nh\u00a0\u00a0\u00a0C. 18 \u0111\u1ec9nh\u00a0\u00a0\u00a0D. 20 \u0111\u1ec9nh<\/p>\n
C\u00e2u 3:<\/b>\u00a0Trong c\u00e1c m\u1ec7nh \u0111\u1ec1 sau, m\u1ec7nh \u0111\u1ec1 n\u00e0o sai ?<\/p>\n
A. S\u1ed1 m\u1eb7t c\u1ee7a m\u1ed9t h\u00ecnh \u0111a di\u1ec7n \u0111\u1ec1u lu\u00f4n l\u00e0 s\u1ed1 ch\u1eb5n<\/p>\n
B. S\u1ed1 \u0111\u1ec9nh c\u1ee7a m\u1ed9t h\u00ecnh \u0111a di\u1ec7n \u0111\u1ec1u lu\u00f4n l\u00e0 s\u1ed1 ch\u1eb5n<\/p>\n
C. S\u1ed1 c\u1ea1nh c\u1ee7a m\u1ed9t h\u00ecnh \u0111a di\u1ec7n \u0111\u1ec1u lu\u00f4n l\u00e0 s\u1ed1 ch\u1eb5n<\/p>\n
D. T\u1ed3n t\u1ea1i m\u1ed9t h\u00ecnh \u0111a di\u1ec7n \u0111\u1ec1u c\u00f3 s\u1ed1 c\u1ea1nh l\u00e0 s\u1ed1 l\u1ebb<\/p>\n
C\u00e2u 1:<\/b>\u00a0Trong c\u00e1c m\u1ec7nh \u0111\u1ec1 sau, m\u1ec7nh \u0111\u1ec1 n\u00e0o sai?<\/p>\n
A. Kh\u1ed1i l\u1eadp ph\u01b0\u01a1ng l\u00e0 kh\u1ed1i \u0111a di\u1ec7n l\u1ed3i<\/p>\n
B. Kh\u1ed1i ch\u00f3p l\u00e0 kh\u1ed1i \u0111a di\u1ec7n l\u1ed3i<\/p>\n
C. Kh\u1ed1i l\u0103ng tr\u1ee5 l\u00e0 kh\u1ed1i \u0111a di\u1ec7n l\u1ed3i<\/p>\n
D. Gh\u00e9p hai kh\u1ed1i \u0111a di\u1ec7n l\u1ed3i s\u1ebd \u0111\u01b0\u1ee3c m\u1ed9t kh\u1ed1i \u0111a di\u1ec7n l\u1ed3i<\/p>\n
C\u00e2u 2:<\/b>\u00a0Trong c\u00e1c m\u1ec7nh \u0111\u1ec1 sau, m\u1ec7nh \u0111\u1ec1 n\u00e0o \u0111\u00fang?<\/p>\n
A. Kh\u1ed1i \u0111a di\u1ec7n \u0111\u1ec1u lo\u1ea1i (p;q) l\u00e0 kh\u1ed1i \u0111a di\u1ec7n c\u00f3 c\u00e1c t\u00ednh ch\u1ea5t sau:<\/p>\n
a) M\u1ed7i m\u1eb7t c\u1ee7a n\u00f3 l\u00e0 m\u1ed9t \u0111a gi\u00e1c \u0111\u1ec1u<\/p>\n
b) M\u1ed7i \u0111\u1ec9nh c\u1ee7a n\u00f3 l\u00e0 \u0111\u1ec9nh chung c\u1ee7a \u0111\u00fang q m\u1eb7t<\/p>\n
B. Kh\u1ed1i \u0111a di\u1ec7n \u0111\u1ec1u lo\u1ea1i (p;q) l\u00e0 kh\u1ed1i \u0111a di\u1ec7n c\u00f3 c\u00e1c t\u00ednh ch\u1ea5t sau:<\/p>\n
a) M\u1ed7i m\u1eb7t c\u1ee7a n\u00f3 l\u00e0 m\u1ed9t \u0111a gi\u00e1c \u0111\u1ec1u p c\u1ea1nh<\/p>\n
b) M\u1ed7i c\u1ea1nh c\u1ee7a n\u00f3 l\u00e0 c\u1ea1nh chung c\u1ee7a \u0111\u00fang hai m\u1eb7t<\/p>\n
C. Kh\u1ed1i \u0111a di\u1ec7n \u0111\u1ec1u lo\u1ea1i (p;q) l\u00e0 kh\u1ed1i \u0111a di\u1ec7n c\u00f3 c\u00e1c t\u00ednh ch\u1ea5t sau:<\/p>\n
a) M\u1ed7i m\u1eb7t c\u1ee7a n\u00f3 l\u00e0 m\u1ed9t \u0111a gi\u00e1c \u0111\u1ec1u p c\u1ea1nh<\/p>\n
b) M\u1ed7i \u0111\u1ec9nh c\u1ee7a n\u00f3 l\u00e0 \u0111\u1ec9nh chung c\u1ee7a \u0111\u00fang q m\u1eb7t<\/p>\n
D. Kh\u1ed1i \u0111a di\u1ec7n \u0111\u1ec1u lo\u1ea1i (p;q) l\u00e0 kh\u1ed1i \u0111a di\u1ec7n c\u00f3 c\u00e1c t\u00ednh ch\u1ea5t sau:<\/p>\n
a) M\u1ed7i m\u1eb7t c\u1ee7a n\u00f3 l\u00e0 m\u1ed9t \u0111a gi\u00e1c \u0111\u1ec1u p c\u1ea1nh<\/p>\n
b) M\u1ed7i \u0111\u1ec9nh c\u1ee7a n\u00f3 l\u00e0 \u0111\u1ec9nh chung c\u1ee7a \u0111\u00fang q m\u1eb7t<\/p>\n
C\u00e2u 3:<\/b>\u00a0Kh\u1ed1i l\u1eadp ph\u01b0\u01a1ng l\u00e0 kh\u1ed1i \u0111a di\u1ec7n \u0111\u1ec1u thu\u1ed9c lo\u1ea1i n\u00e0o?<\/p>\n
A. (4; 3)\u00a0\u00a0\u00a0B. (3; 4)\u00a0\u00a0\u00a0C. (5; 3)\u00a0\u00a0\u00a0D. (3; 5)<\/p>\n
C\u00e2u 4:<\/b>\u00a0Kh\u1ed1i b\u00e1t di\u1ec7n l\u00e0 kh\u1ed1i \u0111a di\u1ec7n \u0111\u1ec1u thu\u1ed9c lo\u1ea1i n\u00e0o?<\/p>\n
A. (4; 3)\u00a0\u00a0\u00a0B. (3; 4)\u00a0\u00a0\u00a0C. (5; 3)\u00a0\u00a0\u00a0D. (3; 5)<\/p>\n
H\u01b0\u1edbng d\u1eabn gi\u1ea3i v\u00e0 \u0110\u00e1p \u00e1n<\/b><\/p>\n C\u00e2u 1:<\/b><\/p>\n C\u00e1ch 1. D\u1ef1a v\u00e0o l\u00ed thuy\u1ebft (nh\u1eadn x\u00e9t c)<\/p>\n C\u00e1ch 2. M\u1ed7i m\u1eb7t c\u1ee7a n\u00f3 l\u00e0 tam gi\u00e1c \u0111\u1ec1u n\u00ean s\u1ed1 c\u1ea1nh c\u1ee7a n\u00f3 b\u1eb1ng<\/p>\n <\/p>\n \u0110\u00e1p \u00e1n l\u00e0 C<\/p>\n C\u00e2u 2:<\/b><\/p>\n C\u00e1ch 1. D\u1ef1a v\u00e0o l\u00ed thuy\u1ebft (nh\u1eadn x\u00e9t b)<\/p>\n C\u00e1ch 2. Kh\u1ed1i 12 m\u1eb7t \u0111\u1ec1u thu\u1ed9c lo\u1ea1i (5 ;3) n\u00ean ta c\u00f3 5.12=3d=2c. Suy ra d=20.<\/p>\n \u0110\u00e1p \u00e1n l\u00e0 D<\/p>\n C\u00e2u 3:<\/b><\/p>\n C\u00e1ch 1. D\u1ef1a v\u00e0o l\u00ed thuy\u1ebft (nh\u1eadn x\u00e9t a, b, c)<\/p>\n C\u00e1ch 2. \u00c1p d\u1ee5ng c\u00f4ng th\u1ee9c pm = 2x , thay m = 4, 8, 12, 20, ta th\u1ea5y ngay c ch\u1eb5n. V\u1edbi h\u00ecnh l\u1eadp ph\u01b0\u01a1ng ta c\u00f3 4m = 2c n\u00ean c ch\u1eb5n.<\/p>\n Suy ra D l\u00e0 m\u1ec7nh \u0111\u1ec1 sai.<\/p>\n C\u00e2u 1:<\/b><\/p>\n H\u00ecnh t\u1ea1o b\u1edfi hai h\u00ecnh ch\u00f3p c\u00f3 chung m\u1ed9t \u0111\u1ec9nh duy nh\u1ea5t kh\u00f4ng ph\u1ea3i l\u00e0 kh\u1ed1i \u0111a di\u1ec7n l\u1ed3i. Suy ra D sai.<\/p>\n C\u00e2u 2:<\/b><\/p>\n D\u1ef1a v\u00e0o \u0111\u1ecbnh ngh\u0129a kh\u1ed1i \u0111a di\u1ec7n \u0111\u1ec1u.<\/p>\n C\u00e2u 3:<\/b><\/p>\n C\u00e1c b\u00e0i t\u1eadp t\u1eeb 3 \u0111\u1ebfn 9 s\u1eed d\u1ee5ng nh\u1eadn x\u00e9t \u1edf ph\u1ea7n A. C\u00e1c b\u00e0i t\u1eadp 7,8,9 c\u0169ng c\u00f3 th\u1ec3 d\u00f9ng c\u00f4ng th\u1ee9c (2), (3), v\u00ed d\u1ee5 b\u00e0i t\u1eadp 9 : c\u00e1c m\u1eb7t c\u1ee7a kh\u1ed1i 20 m\u1eb7t \u0111\u1ec1u l\u00e0 nh\u1eefng tam gi\u00e1c n\u00ean ta c\u00f3 2.30=2c, suy ra c=30.<\/p>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":" C\u00e2u 1:\u00a0Kh\u1ed1i 20 m\u1eb7t \u0111\u1ec1u c\u00f3 bao nhi\u00eau c\u1ea1nh? A. 24 c\u1ea1nh \u00a0\u00a0\u00a0B. 28 c\u1ea1nh\u00a0\u00a0\u00a0C. 30 c\u1ea1nh\u00a0\u00a0\u00a0D. 40 c\u1ea1nh C\u00e2u 2:\u00a0Kh\u1ed1i 12 m\u1eb7t \u0111\u1ec1u c\u00f3 bao nhi\u00eau \u0111\u1ec9nh ? A. 10 \u0111\u1ec9nh\u00a0\u00a0\u00a0B. 12 \u0111\u1ec9nh\u00a0\u00a0\u00a0C. 18 \u0111\u1ec9nh\u00a0\u00a0\u00a0D. 20 \u0111\u1ec9nh C\u00e2u 3:\u00a0Trong c\u00e1c m\u1ec7nh \u0111\u1ec1 sau, m\u1ec7nh \u0111\u1ec1 n\u00e0o sai ? A. S\u1ed1 m\u1eb7t c\u1ee7a m\u1ed9t h\u00ecnh […]<\/p>\n","protected":false},"author":3,"featured_media":28955,"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 1-C<\/td>\n 2-D<\/td>\n 3-D<\/td>\n 1-D<\/td>\n 2-D<\/td>\n 3-A<\/td>\n 4-B<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n