1. 35−85+55=3−8+55=05=035−85+55=3−8+55=05=𝟎
2. 54−34+54=5−3+54=7454−34+54=5−3+54=𝟕𝟒
3. 37−87−147=3−8−147=−19737−87−147=3−8−147=−𝟏𝟗𝟕
4. 712⋅18-14=7⋅1812⋅(-14)=1⋅32⋅(-2)=−34712⋅18−14=7⋅1812⋅(−14)=1⋅32⋅(−2)=−𝟑𝟒
5. -2421∶-814=-87⋅-148=-8⋅(-14)7⋅8=2−2421∶−814=−87⋅−148=−8⋅(−14)7⋅8=𝟐
6. -72+34+916+42=(-72+42)+1216+916=−32+2116=-24+2116=−316−72+34+916+42=(−72+42)+1216+916=−32+2116=−24+2116=−𝟑𝟏𝟔

1. (27+57)+(35+75)+(918)=1+2+12=312(27+57)+(35+75)+(918)=1+2+12=𝟑𝟏𝟐 hoặc  72𝟕𝟐
2. 510−1113+910−813=(510+910)−(1113+813)=1410−1913=75−1913=91−9565=−465510−1113+910−813=(510+910)−(1113+813)=1410−1913=75−1913=91−9565=−𝟒𝟔𝟓
3. 523⋅712⋅235=(523⋅235)⋅712=1⋅712=712523⋅712⋅235=(523⋅235)⋅712=1⋅712=𝟕𝟏𝟐
4. 53⋅(1113+213)=53⋅1=5353⋅(1113+213)=53⋅1=𝟓𝟑
5. 213⋅(55−85)+213⋅5=213⋅(−35+5)=213⋅225=4465213⋅(55−85)+213⋅5=213⋅(−35+5)=213⋅225=𝟒𝟒𝟔𝟓
6. 13⋅(411+811−1)=13⋅(1211−1)=13⋅111=13313⋅(411+811−1)=13⋅(1211−1)=13⋅111=𝟏𝟑𝟑
7. (718+1118)−(512)=1−512=712(718+1118)−(512)=1−512=𝟕𝟏𝟐
8. 2417−(717+116)=(2417−717)−116=1−116=15162417−(717+116)=(2417−717)−116=1−116=𝟏𝟓𝟏𝟔

1. �=(1−12)+(12−13)+…+(199−1100)=1−1100=99100𝐴=(1−12)+(12−13)+…+(199−1100)=1−1100=𝟗𝟗𝟏𝟎𝟎
2. �=(1−13)+(13−15)+…+(199−1101)=1−1101=100101𝐵=(1−13)+(13−15)+…+(199−1101)=1−1101=𝟏𝟎𝟎𝟏𝟎𝟏
3. �=(3−11⋅3)+(6−33⋅6)+…+(66−5555⋅66)=(1−13)+(13−16)+…+(155−166)=1−166=6566𝑀=(3−11⋅3)+(6−33⋅6)+…+(66−5555⋅66)=(1−13)+(13−16)+…+(155−166)=1−166=𝟔𝟓𝟔𝟔
4. �=11⋅2+12⋅3+…+110⋅11=1−111=1011𝐶=11⋅2+12⋅3+…+110⋅11=1−111=𝟏𝟎𝟏𝟏
5. �=23⋅(32⋅5+35⋅8+…+314⋅17)=23⋅(12−117)=23⋅1534=517𝐷=23⋅(32⋅5+35⋅8+…+314⋅17)=23⋅(12−117)=23⋅1534=𝟓𝟏𝟕
6. Sử dụng công thức  1�(�+1)(�+2)=12(1�(�+1)−1(�+1)(�+2))1𝑛(𝑛+1)(𝑛+2)=12(1𝑛(𝑛+1)−1(𝑛+1)(𝑛+2)):
   Tổng  =12(11⋅2−12⋅3+12⋅3−…−198⋅99)=12(12−19702)=12⋅48509702=24259702=12(11⋅2−12⋅3+12⋅3−…−198⋅99)=12(12−19702)=12⋅48509702=𝟐𝟒𝟐𝟓𝟗𝟕𝟎𝟐

• Dạng 1: 0,  7474,  −197−197,  −34−34, 2,  −316−316
• Dạng 2:  7272,  −465−465,  712712,  5353,  44654465,  133133,  712712,  15161516
• Dạng 3:  9910099100,  100101100101,  65666566,  10111011,  517517,  2425970224259702

tôi giải rồi nè

➡️ Bước 1: Giải các phép tính cơ bản (Dạng 1)

1. 35−85+55=3−8+55=05=035−85+55=3−8+55=05=𝟎
2. 54−34+54=5−3+54=7454−34+54=5−3+54=𝟕𝟒
3. 37−87−147=3−8−147=−19737−87−147=3−8−147=−𝟏𝟗𝟕
4. 712⋅18-14=7⋅1812⋅(-14)=1⋅32⋅(-2)=−34712⋅18−14=7⋅1812⋅(−14)=1⋅32⋅(−2)=−𝟑𝟒
5. -2421∶-814=-87⋅-148=-8⋅(-14)7⋅8=2−2421∶−814=−87⋅−148=−8⋅(−14)7⋅8=𝟐
6. -72+34+916+42=(-72+42)+1216+916=−32+2116=-24+2116=−316−72+34+916+42=(−72+42)+1216+916=−32+2116=−24+2116=−𝟑𝟏𝟔

➡️ Bước 2: Tính nhanh bằng tính chất (Dạng 2)

1. (27+57)+(35+75)+(918)=1+2+12=312(27+57)+(35+75)+(918)=1+2+12=𝟑𝟏𝟐 hoặc  72𝟕𝟐
2. 510−1113+910−813=(510+910)−(1113+813)=1410−1913=75−1913=91−9565=−465510−1113+910−813=(510+910)−(1113+813)=1410−1913=75−1913=91−9565=−𝟒𝟔𝟓
3. 523⋅712⋅235=(523⋅235)⋅712=1⋅712=712523⋅712⋅235=(523⋅235)⋅712=1⋅712=𝟕𝟏𝟐
4. 53⋅(1113+213)=53⋅1=5353⋅(1113+213)=53⋅1=𝟓𝟑
5. 213⋅(55−85)+213⋅5=213⋅(−35+5)=213⋅225=4465213⋅(55−85)+213⋅5=213⋅(−35+5)=213⋅225=𝟒𝟒𝟔𝟓
6. 13⋅(411+811−1)=13⋅(1211−1)=13⋅111=13313⋅(411+811−1)=13⋅(1211−1)=13⋅111=𝟏𝟑𝟑
7. (718+1118)−(512)=1−512=712(718+1118)−(512)=1−512=𝟕𝟏𝟐
8. 2417−(717+116)=(2417−717)−116=1−116=15162417−(717+116)=(2417−717)−116=1−116=𝟏𝟓𝟏𝟔

➡️ Bước 3: Tính tổng các dãy số quy luật (Dạng 3)

1. �=(1−12)+(12−13)+…+(199−1100)=1−1100=99100𝐴=(1−12)+(12−13)+…+(199−1100)=1−1100=𝟗𝟗𝟏𝟎𝟎
2. �=(1−13)+(13−15)+…+(199−1101)=1−1101=100101𝐵=(1−13)+(13−15)+…+(199−1101)=1−1101=𝟏𝟎𝟎𝟏𝟎𝟏
3. �=(3−11⋅3)+(6−33⋅6)+…+(66−5555⋅66)=(1−13)+(13−16)+…+(155−166)=1−166=6566𝑀=(3−11⋅3)+(6−33⋅6)+…+(66−5555⋅66)=(1−13)+(13−16)+…+(155−166)=1−166=𝟔𝟓𝟔𝟔
4. �=11⋅2+12⋅3+…+110⋅11=1−111=1011𝐶=11⋅2+12⋅3+…+110⋅11=1−111=𝟏𝟎𝟏𝟏
5. �=23⋅(32⋅5+35⋅8+…+314⋅17)=23⋅(12−117)=23⋅1534=517𝐷=23⋅(32⋅5+35⋅8+…+314⋅17)=23⋅(12−117)=23⋅1534=𝟓𝟏𝟕
6. Sử dụng công thức  1�(�+1)(�+2)=12(1�(�+1)−1(�+1)(�+2))1𝑛(𝑛+1)(𝑛+2)=12(1𝑛(𝑛+1)−1(𝑛+1)(𝑛+2)):
   Tổng  =12(11⋅2−12⋅3+12⋅3−…−198⋅99)=12(12−19702)=12⋅48509702=24259702=12(11⋅2−12⋅3+12⋅3−…−198⋅99)=12(12−19702)=12⋅48509702=𝟐𝟒𝟐𝟓𝟗𝟕𝟎𝟐

✅ Trả lời: Kết quả các bài toán lần lượt là:

• Dạng 1: 0,  7474,  −197−197,  −34−34, 2,  −316−316
• Dạng 2:  7272,  −465−465,  712712,  5353,  44654465,  133133,  712712,  15161516
• Dạng 3:  9910099100,  100101100101,  65666566,  10111011,  517517,  2425970224259702

Thế thì chịu ròi ^_^

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