`\sqrt{x^2+x+1}=1`
⇔`(\sqrt{x^2+x+1})^2=1^2`
⇔`x^2+x+1=1`
⇔`x^2+x=0`
⇔`x(x+1)=0`
⇔\(\left[ \begin{array}{l}x=0\\x+1=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=0\\x=-1\end{array} \right.\)
Biểu thức trong căn luôn lớn hơn 0 với mọi x
Bình phương hai vế ta được
X^2 + x + 1 = 0
x^2 + x = 0
x(x + 1) = 0
Vậy x = 0 hoặc x = -1
biết 25% của mọt số là 90. Vậy 1phần 5 của số đó là giá trị của x trông biểu thức 4 phần x =2 phần 3 là
Câu 1: Thành tựu quan trọng nhất của Người nguyên thủy trong quá trình chế tạo công cụ và vũ khí là A. Lưới đánh cá. B. Làm đồ gốm. C. Cung tên. D. Đá mài sắc, gọn.
Bài 1. Có 6 nhóm học sinh tham gia thi (mỗi nhóm có số bạn bằng nhau). Các e đều được điểm 10 hoặc 8. Tổng số điểm đạt đc là 160 điểm. Hỏi có bao nhiêu bạn được 10, bao nhiêu bạn được 8?
Correct words : 1 It wasn't a big (succeed) 2 It is a (legal)for children to drive in Vn 3 Have you got (drive) liense ? 4 Stop in front of the zebra (cross) 5 waves will be used as an (environment ) friendly sources of energy 6 I have never felt as (terrify) As i did 7 He is a (disappiont) man he is lazy and drunk all day 8 solar energy is renewable (plenty ) and clean 9 We should reduce the use of (electric) at home 10 They found his behavior (annoy) Ghi giúp mình công thức luôn nha cảm ơn:>
NHÀ EM CÁI THÁI DƯƠNG NĂNG NÓ CỨ PHUN NƯỚC RA NGOÀI LÀ THẾ NÀO Ạ? VÀ NÓ GÂY RA HẬU QUẢ GÌ?
cho hàm số (C) y=(2x-1)/(x-1).Gọi I có tọa độ I(1,2).Tìm điểm M thuộc (C) sao cho tiếp tuyến của (C) tại M vuông góc với đường thẳng IM GIÚP EM GIẢI THÍCH BÀI NÀY VỚI Ạ EM CẢM ƠN!!!!!!
Tính: 1) [(a+b) -c] ² 2) (a-b+c) ² 3) (a-b-c) ² 4) (a+b+c+d)² Mọi người giúp mình nha mai nộp r. Thanks!
trình bày chuyển biến xã hội thời kỳ bắc thuộc, so với thời kỳ trước có điều gì khác
5 sao và câu trả lời nhanh nhất Nhớ phải chi tiết nhé Ai trả lời ko chi tiết hoặc chép mạng đạt từ 1-3 sao thôi
VIII. Read the following passage and choose the best answer for each question. Do you ever think about what schools will be like in the future? Many people think that students will study most regular classes such as maths, science and history online. Students will probably be able to these subjects anywhere using a computer. What will happen if students have problems with a subject? They might connect with a teacher through live videoconferencing. Expert teachers from learning centres will give students help wherever they live. Students will still take classes in a school, too. Schools will become places for learning social skills. Teachers will guide students in learning how to work together in getting along with each other. They will help students with group projects both in and out of the classroom. Volunteer work and working at local businesses will teach students important life skills about the world they live in. This will help students become an important part of their communities. Some experts say it will take five years for changes to begin in schools. Some say it will take longer. Most people agree, though, that computers will change education the way TVs and telephones changed life for people all over the world years before. 1. What will happen if students meet difficulties with a subject? A. Teachers from learning centres will give them help through live videoconferencing. B. They will meet their teachers in person for help with problems with the subject. C. They will telephone the teachers who are staying at the school to seek their help. D. Schools will organise a live videoconference for teachers to help students with problems. 2. Students will still go to school to _____ . A. Learn all subjects B. Play with their friends C. Use computers D. Learn social skills 3. The main role of teachers in the future will be _____ . A. Providing students with knowledge B. Guiding students to learn computers C. Helping students with group projects D. Organising live videoconferences 4. Students will learn important life skills through _______ . A. Going to school every day B. Taking online classes C. Working in international businesses D. Doing volunteer work 5. What is the main idea of the passage? A. Kids won’t have to go to school in the future. B. Computers will change education in the future. C. All classes will be taught online in the future. D. Teachers will help students from home in the future. IX. Find a mistake in the four underlined parts of each sentence and correct it. X. Use the words given and other words, complete the second sentence so that it has a similar meaning to the first sentence. Do not change the word given. (Use 2 – 5 words in total). 1. My school is over 100 years old. which I’m studying ________________________ over 100 years old. 2. Students will share their thoughts about the dream school on the forum, on Students’ thoughts about the dream school ________________________the forum. 3. Ms. Kelly, our school principal, will attend our class this afternoon, is Ms. Kelly, ___________________________ , will attend our class this afternoon. 4. Homework will be sent through cyberspace, through Students _______________________ cyberspace. 5. The teacher meeting you yesterday is supervising our project, who The teacher ____________________________ is supervising our project. XI. Choose from 2 to 4 ideas below to write a paragraph of around 100 words about the role of teachers in the future. Teachers’ roles in the future: • Instructional designer • Trainer • Collaborator • Silent partner • Coordinator • Facilitator ________________________________________________________ ________________________________________________________ ________________________________________________________ ________________________________________________________ ________________________________________________________
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