B\u1ea1n \u0111\u00e3 bi\u1ebft ph\u01b0\u01a1ng ph\u00e1p \u0111\u00e1nh l\u00f4 \u0111\u1ec1 online hi\u1ec7u qu\u1ea3 n\u00e0o ch\u01b0a? Hi\u1ec7n nay c\u00f3 2 ph\u01b0\u01a1ng ph\u00e1p ch\u01a1i l\u00f4 \u0111\u1ec1 online d\u1ec5 tr\u00fang nh\u1ea5t \u0111ang \u0111\u01b0\u1ee3c r\u1ea5t nhi\u1ec1u ng\u01b0\u1eddi ch\u01a1i \u00e1p d\u1ee5ng \u0111\u00f3 l\u00e0 ph\u01b0\u01a1ng ph\u00e1p 3 c\u00e2y v\u00e0 ph\u01b0\u01a1ng ph\u00e1p bi\u00ean l\u00f4 hai \u0111\u1ea7u. Tuy nhi\u00ean \u0111\u1ec3 ng\u01b0\u1eddi ch\u01a1i n\u1eafm b\u1eaft v\u00e0 x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c ch\u1eef s\u1ed1 trong con \u0111\u1ec1 d\u1ef1 \u0111\u1ecbnh \u0111\u00e1nh, ch\u00fang t\u00f4i s\u1ebd gi\u1edbi thi\u1ec7u m\u1ed7i ph\u01b0\u01a1ng ph\u00e1p th\u00e0nh m\u1ed9t b\u00e0i vi\u1ebft ri\u00eang bi\u1ec7t.Trong b\u00e0i vi\u1ebft n\u00e0y ch\u00fang t\u00f4i s\u1ebd gi\u1edbi thi\u1ec7u \u0111\u1ebfn c\u00e1c b\u1ea1n ph\u01b0\u01a1ng ph\u00e1p 3 c\u00e2y khi ch\u01a1i l\u00f4 \u0111\u1ec1.<\/p>\n\n\n\n
V\u00ed d\u1ee5: X\u1ebfp 2 s\u1ed1 \u0111\u1ec1 ra trong hai ng\u00e0y 15\/9 v\u00e0 16\/9.<\/p>\n\n\n\n
Ng\u00e0y 15\/9 \u0111\u1ec1 ra 32<\/p>\n\n\n\n
Ng\u00e0y 16\/9 \u0111\u1ec1 ra 22<\/p>\n\n\n\n
\u1ede ph\u01b0\u01a1ng ph\u00e1p n\u00e0y gi\u00fap b\u1ea1n t\u00ecm ra s\u1ed1 \u0111\u1ec1 ra ng\u00e0y ti\u1ebfp theo \u0111\u00f3 l\u00e0 ng\u00e0y 17\/9 \u0111\u1ec1 ra XX. \u0110\u1ec3 t\u00ecm ra \u0111\u01b0\u1ee3c s\u1ed1 X, ch\u00fang ta c\u00f3 th\u1ec3 \u00e1p d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p c\u1ed9ng b\u00f9: Ng\u01b0\u1eddi ch\u01a1i l\u1ea5y m\u1ed9t ch\u1eef s\u1ed1 c\u1ee7a ng\u00e0y th\u1ee9 1c\u1ed9ng v\u1edbi m\u1ed9t ch\u1eef s\u1ed1 c\u1ee7a ng\u00e0y th\u1ee9 2 v\u00e0 c\u1ed9ng v\u1edbi X sao cho k\u1ebft qu\u1ea3 b\u1eb1ng 10 ho\u1eb7c b\u1eb1ng 20.<\/p>\n\n\n\n
V\u1edbi v\u00ed d\u1ee5 tr\u00ean ta c\u00f3 3+2+X=10 ho\u1eb7c 20 ->X=5<\/p>\n\n\n\n
2+2+X = 10 ho\u1eb7c 20 -> X=6<\/p>\n\n\n\n
V\u00ed d\u1ee5:<\/p>\n\n\n\n
Ng\u00e0y 15\/09 k\u1ebft qu\u1ea3 gi\u1ea3i \u0111\u1eb7c bi\u1ec7t: 58432 ta l\u1ea5y 52<\/p>\n\n\n\n
Ng\u00e0y 16\/9 k\u1ebft qu\u1ea3 gi\u1ea3i \u0111\u1eb7c bi\u1ec7t: 73122 ta l\u1ea5y 72<\/p>\n\n\n\n
Ph\u01b0\u01a1ng ph\u00e1p 3 c\u00e2y \u0111\u00e1nh l\u00f4 \u0111\u1ec1 nh\u01b0 sau:<\/p>\n\n\n\n
5+7+X = 10 ho\u1eb7c 20 -> X=8<\/p>\n\n\n\n
5+2+X = 10 ho\u1eb7c 20 -> X=3<\/p>\n\n\n\n
2+7+X = 10 ho\u1eb7c 20 -> X=1<\/p>\n\n\n\n
2+2+X = 10 ho\u1eb7c 20 -> X=6<\/p>\n\n\n\n
Nh\u01b0 v\u1eady v\u1edbi ph\u01b0\u01a1ng ph\u00e1p t\u00ednh nh\u01b0 tr\u00ean ch\u00fang ta c\u00f3 th\u1ec3 d\u1ec5 d\u00e0ng t\u00ecm ra c\u00e1c k\u1ebft qu\u1ea3 X t\u1eeb v\u00ed d\u1ee5 l\u00e0 nh\u1eefng s\u1ed1 1, 3, 5, 6, 8 \u0111\u1ec3 \u1ee9ng d\u1ee5ng v\u00e0o b\u1eaft con \u0111\u1ec1 s\u1ebd v\u1ec1 trong ng\u00e0y 17\/09. L\u01b0u \u00fd \u0111\u1ebfn nh\u1eefng con s\u1ed1 tr\u00f9ng nhau v\u00e0 th\u01b0\u1eddng s\u1ebd c\u00f3 1-3 con s\u1ed1 \u0111\u00f3. K\u1ebft qu\u1ea3 v\u1ec1 nh\u01b0 th\u1ebf n\u00e0o b\u1ea1n c\u0169ng bi\u1ebft r\u1ed3i \u0111\u00f3.<\/p>\n\n\n\n
\u0110\u1ebfn \u0111\u00e2y s\u1ebd c\u00f3 ng\u01b0\u1eddi ch\u01a1i \u0111\u01b0a ra c\u00e2u h\u1ecfi, c\u00e1i n\u00e0y ch\u1ec9 t\u00ecm \u0111\u01b0\u1ee3c ra 4 c\u00e2y n\u1eb1m trong c\u1ea3 s\u1ed1 \u0111\u1ea7u, s\u1ed1 \u0111\u00edt c\u1ee7a con \u0111\u1ec1 v\u00e0 hi\u1ec7u qu\u1ea3 ch\u01b0a th\u1ef1c s\u1ef1 ho\u00e0n h\u1ea3o. Qu\u1ea3 \u0111\u00fang l\u00e0 nh\u01b0 v\u1eady, v\u00ec m\u1ed9t ng\u01b0\u1eddi ch\u01a1i chuy\u00ean nghi\u1ec7p s\u1ebd kh\u00f4ng ch\u1ecbu d\u1eebng t\u1ea1i \u0111\u00e2y. M\u00e0 c\u00f2n c\u00f3 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p kh\u00e1c n\u1eefa \u0111\u1ec3 t\u00ecm ra nh\u1eefng con s\u1ed1 t\u1ed1t nh\u1ea5t trong m\u1ed9t d\u00e3y s\u1ed1. \u1ede b\u00e0i vi\u1ebft sau s\u1ebd gi\u1edbi thi\u1ec7u \u0111\u1ebfn c\u00e1c b\u1ea1n m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p ch\u01a1i l\u00f4 \u0111\u1ec1 d\u1ec5 ch\u01a1i d\u1ec5 tr\u00fang nh\u1ea5t.<\/p>\n\n\n\n
V\u1edbi ph\u01b0\u01a1ng ph\u00e1p tr\u00ean, n\u1ebfu b\u1ea1n \u00e1p d\u1ee5ng thu\u1ea7n th\u1ee5c . B\u1ea1n s\u1ebd ki\u1ebfm v\u1ec1 kh\u00f4ng \u00edt l\u1ee3i nhu\u1eadn r\u1ed3i, n\u00ean \u0111i t\u1eeb c\u00e1i d\u1ec5 tr\u01b0\u1edbc b\u1ea1n nh\u00e9. Ch\u00fac c\u00e1c b\u1ea1n ch\u01a1i vui v\u1ebb.<\/p>\n\r\n