a) sin3x - 2cos^2x = -1 b) cos3x+ cosx = 2căn3cos2x.sinx Giúp e câu a nữa với ạ. tks mn e cần gấp ạ

Đây nhé lúc nãy mình chụp hơi thiếu

Bằng một bài văn ngắn, em hãy bày tỏ suy nghĩ của mình về nghĩa đồng bào, tình đồng bào được nhắc đến qua những cử chỉ của nhà nước khi có người dân ở các nước Châu Âu khi có đại dịch covid-19 hoành hành. Viết cả bài ra cho mình nha!

1,Một hình tròn có r = 8cm thì có chu vi là ….cm ? A) 50,24 B) 25,12 C) 12,56 D) 200,96 2,Một hình tòn có d = 6dm thì có diện tích là ….dm 2 ? A) 113,04 B) 18,84 C) 28,26 D) 28,36 3,Biết 2/5 số bi trong hộp là 12 viên. Vậy hộp bi có tất cả bao nhiêu viên bi ? A) 18 B) 24 C) 60 D) 30 4,(1,5đ)Một bể cá hình hộp chữ nhật có chiều dài 0,5m, chiều rộng 0,3m. Trong bể chứa 48 lít nước và mực nước lên đến4/5 chiều cao của bể. Tính chiều cao của bể.

42. She used a pencil ……………… this letter. (write) 43. Maria ……………… studying English for 5 years, now she ……………… it yet. (study / master) 44. This book ………………… to me yesterday. (send) 45. If you come here in Spring, you ……………… a chance to go to the village fair. (have) 46. The books in the library ……………………… into sections. (arrange) 47. The card catalogue is helpful in ………………… the books you find. (find) 48. Nam ………………. a gold medal in the chess tournament last week. (win) 49. The tree in our garden should ……………………. every day. (water) 50. If I finish my work soon, I …………………… for a drink with you. (come) 51. The rocket ……………………… around the Earth for 30 minutes. (fly) 52. The weather …………………. terrible since yesterday. (be) 53. You must take the baby to the doctor’s if his temperature ………… up again. (go) 54. If Jack ……………… a video recorder, he ………………. many programs. (have / record) 55. All the students are looking forward ………………………… summer vacation. (spend) 56. Justin said he …………………. the following day. (return) 57. The teacher ordered Tom …………… to the blackboard. (go) 58. Tam’s mother advises her ………… (not spend) too much time on ………. computer games. (play) 59. When we …………… (go) down the hill, a strange object ……………… (appear) in the sky. 60. The floor isn’t very clean now. Jane …………………… it for 2 hours. (clean) 61. It doesn’t stop raining. It ……………………….. the whole day. (rain) 62. What ………………………….. at this time yesterday ? (you / do) 63. It is ……………… that he …………………… here now. (suggest / be) 64. This car …………………….. if it is cheap. (buy) 65. The robber climbed into the windows without ……………………… (see) 66. Do you suggest ………………… on the grass enjoying sunshine ? (lie) 67. Those environmentalists are happy ……………… the battle against dynamite fishing. (win) 68. In order to save electricity, an ordinary 100-watt bulb can …… by an energy-saving bulb. (replace) 69. Ha ……………………. herself for quite a long time. (enjoy) 70. On the way home, Long often stops ………………… a newspaper. (buy)

rút gọn biểu thức B=(((a-1)^2/(3a+(a-1)^2))-((1-2*a^2+4*a)/(a^3-1))+(1/(a-1))/((a^3+4*a)/(4*a^2))

Viết một đoạn văn hội thoại ngắn về chủ đề"học tập".Trong đoạn sử dụng 2 trong các kiểu câu sau:nghi vấn,cầu khiến,cảm thán,trần thuật,phủ định.((không chép mạng mình sẽ đánh giá 5☆))

V- Give the correct form of the words in brackets to complete the following sentences 31. Don’t make a fire here. It’s very ...................... . danger 32. Air .................... is a big problem in many cities in the world. pollute 33. There are a lot of .................... mountains in VietNam. beauty 34. I’m Vietnamese. What’s your .......................... ? nation 35. We must be ................... when we cross the road. care VI- Rewrite these sentences that it means the same as the sentence printed before it. 36. My room is smaller than your room. Your room is………………………………………………………… 37. Mr. Hung drives very carefully. Mr. Hung is .................................................................. 38. Does Phong’s school have forty classrooms ? Are …………………………………………? 39. Does your father cycle to work? Does your father get .......................? 40. How much does a box of chocolates cost? What ...........................................................? 41. Nam likes tea. Nam’s favorite ....................... 42. The Mekong River is longer than the Red River. The Red River is ………………………………………… 43. How much is a bowl of noodles ? How much does………………………………………..? 44. What is the height of that building? How ............................................... 45. What is the price of a cake and an orange ? How much …………………………………………..?

Bài 1: Hãy tính số nguyên tử có trong các lượng chất sau: a, 0,75 mol nguyên tử Fe b, 1,4 molnguyeen tử C c, 0,1 mol nguyên tủ H d, 0,15 mol nguyên tử Cu Bài 2 : Tính số mol các chất sau: a, 0,65g Zn b, 10g CaCO3 c, 22,4g CaO d, 0,48g Cacbon

III- Complete the sentences with the correct form of the verbs in brackets. 16. How much fruit that farmer (produce)....................every year? 17. We (waste) ................ too much power at the moment. 18. He (buy) ................. a new house next month ? 19. The Nile River is the longest river in the world and it (flow) ....... to the Mediterian Sea. 20. Mr and Mrs Thinh ( not grow ) ........................ vegetables in their garden. IV- Fill one suitable word in each gap to complete the following passage. We are destroying the Earth. The seas and rivers are (21)......... dirty to swim in. There (22)............ too smoke in the air in many cities in the world, we are cutting (23)...........too many trees. We (24) ............ burning the forests. We are also destroying (25)............ of plants and (26)......... . Many areas(27)...........Earth are wasteland. Farmers in many parts of the world can not (28) ........... enough to eat. In some countries (29).......... is too little rice. The Earth is in (30).......... . Save the Earth.