A = $\sqrt{7-2√10}$ - $\sqrt{7+2√10}$
A = $\sqrt{(√5-√3)²}$ - $\sqrt{(√5+√3)²}$
A= √5-√3 - √5-√3 = -2√3
`B=` $\frac{1}{√3+2}$ - $\frac{1}{√3-2}$
`B=` $\frac{√3-2-√3-2}{(√3+2)(√3-2)}$
`B=` $\frac{-4}{-1}$ `= 4`
`I=` $\frac{√10-√2}{√5-1}$ - $\frac{2-√2}{√2-1}$
`I=` $\frac{√2(√5-1)}{√5-1}$ - $\frac{√2(√2-1)}{√2-1}$
`I= √2-√2 = 0`
`A=sqrt{7-2sqrt10}-sqrt{7+2sqrt10}``=sqrt{5-2sqrt10+2}-sqrt{5+2sqrt10+2}` `=sqrt{(sqrt5)^2-2*sqrt5*sqrt2+(sqrt2)^2}-sqrt{(sqrt5)^2+2*sqrt5*sqrt2+(sqrt2)^2}``=sqrt{(sqrt5-sqrt2)^2}-sqrt{(sqrt5+sqrt2)^2}``=|sqrt5-sqrt2|-|sqrt5+sqrt2|``=sqrt5-sqrt2-sqrt5-sqrt2` `(Vì ` `sqrt5-sqrt2 >0` `;` `sqrt5+sqrt2)``=-2sqrt2`Vậy `A=-2sqrt2``B=1/(sqrt3+2)-1/(sqrt3-2)``=(sqrt3-2)/((sqrt3+2)(sqrt3-2))-(sqrt3+2)/((sqrt3+2)(sqrt3-2))``=((sqrt3-2)-(sqrt3+2))/((sqrt3+2)(sqrt3-2))``=(sqrt3-2-sqrt3-2)/((sqrt3)^2-2^2)``=(-4)/(3-4)``=(-4)/(-1)``=4`Vậy `B=4``I =(sqrt10 -sqrt2)/(sqrt5-1) -(2-sqrt2)/(sqrt2-1)``=(sqrt2(sqrt5-1))/(sqrt5-1) -(sqrt2(sqrt2-1))/(sqrt2-1)``=sqrt2-sqrt2``=0`Vậy `I=0`
Mn ơi , hộ mình với ( làm hai bài, bài nào cũng được
. Viết lại các câu sao cho nghĩa không đổi, bắt đầu bằng cụm từ cho sẵn. 1. If he has free time, he’ll play tennis.→ Should …………………………………………………….. 2. If she comes early, we’ll start.→ Should ………………………………………………………. 3. They would answer me if they were here.→ Were ……………………………………… 4. If I learnt Russian, I would read a Russian book.→ Were ………………………………… 5. If they lived in Australia now, they would go swimming.→ Were …………………………… 6. If it had rained yesterday, we would have stayed at home. → Had ……………………………………………………………………… 7. If he had trained hard, he would have won the match.→ Had …………………………… 8. If she were not shy, she would have a good time at the party. → Were …………………………………………………………………….. 9. If I hadn’t seen it, I wouldn’t have believed it.→ Had ………………………… 10. If it hadn't been for the traffic, I wouldn't have been late.→ Had it …………………………… 11. Without your help, I wouldn’t pass the exam. → If you ………………………… 12. But for your help, I would die.→ If it …………………
IX. Write the correct form or tense of the verbs in brackets. 1. We (play) football this afternoon. Do you want to play too? 2. Could you meet me at the airport tomorrow? My flight___________(arrive) at six. 3. Last summer, my friends and I ___________(spend) our holiday on a farm. 4. Nick ___________(not ride) a buffalo drawn cart before. 5. The cattle ___________(graze) on the green pastures right now. 6. Millions of Mongolians ___________(be) semi-nomadic herders for thousands of years. 7. My family ___________(live) in a small town for ten years before moving to Boston. 8. Country life ___________(not excite) me at all. It’s so boring. 9. Nick would like ___________(visit) the countryside at the harvest time. 10. I don’t mind ___________(drive) for 1.5 hours on the weekend to get out to the countryside. X. Write the correct form of the word in brackets. 1. People seem to have lost their ___________ in boating on small rivers. (enjoy) 2. More and more ___________are leaving the countryside to city. (farm) 3. A town has a ___________ population than a village does. (large) 4. Sylvia likes the ___________ atmosphere during her stay in the valley. (peace) 5. The firefighters were praised for their ___________ and devotion to duty. (brave) 6. Visually the house is very pleasing, but it’s ___________. (comfort) 7. It is true that the city can provide much ___________. (convenient) 8. Agricultural work is ___________ seen as a male occupation. (tradition) 9. Villages and towns are not as densely ___________ as cities. (populate) 10. The trip was an ___________ experience. We enjoyed it very much! (forget)
nàng bất đắc dĩ nói........ →núi vọng phong kia nữa C1: ghi lại 1 thành ngữ có trong đoạn trích trên C2:nêu và phân tích tác dụng của 1 phép tu từ được sử dụng trong đoạn văn trên cíu!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Cho CaCO3 tác dụng với HCl tạo CaCl2, H2O, sinh ra 6,72 lít khí CO2 ở đktc a.Tính khối lượng CaCl2 sinh ra b. Tính khối lượng CaCO3 đã phản ứng c. Tính khối lượng HCl đã phản ứng
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1 Hòa bình là gì? 2 Bảo vệ hòa bình là gì? 3 Để bảo vệ hòa bình chúng ta phải làm gì? 4 Để thể hiện lòng yêu hòa bình,ngay từ trên ghế nhà trường chúng ta phải làm gì?
Cali: bye bye nl; tạm biệt nhé
Giúp mình với nhé mình đang cần gấp lắm rồi
mn lm hộ em bài 2 từ câu 11 đến câu 18 với ạ
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