Hàm số \(f(x)\) có đạo hàm xác định trên \(\mathbb{R}\) thỏa mãn \(y=f(x)+f(-x)\) đồng biến trên khoảng \((1; 5)\). Khi đó hàm số \(y=f(x)+f(-x)\) nghịch biến trên khoảng nào?
Hãy suy nghĩ và trả lời câu hỏi trước khi xem đáp án
\({{y}^{\prime }}={{f}^{\prime }}(x)-{{f}^{\prime }}(-x)>0\,\,\forall x\in (1;5)\)
Đặt \(x=-t\Rightarrow t\in (-5;-1)\)
\(\begin{align} & \Rightarrow {{f}^{\prime }}(-t)-{{f}^{\prime }}(t)>0\,\,\forall t(-5;-1) \\ & \Leftrightarrow {{f}^{\prime }}(t)-{{f}^{\prime }}(-t)<0\,\,\,\forall t(-5;-1) \\ & \Leftrightarrow {{f}^{\prime }}(x)-{{f}^{\prime }}(-x)<0\,\,\forall x(-5;-1) \\ \end{align}\)
Vậy hàm số \(y=f(x)+f(-x)\) nghịch biến trên \((-3 ;-1)\).
Với cấu trúc mới lạ và đa dạng, Đề Thi Tham Khảo Đánh Giá Năng Lực Năm 2025 – ĐHQG Hà Nội – Đề Số 4 giúp thí sinh phát huy tối đa khả năng Giải Quyết Vấn Đề, Sáng Tạo và Tư Duy Định Lượng. Bài thi bao gồm ba phần chính: Toán Học Và Xử Lí Số Liệu, Văn Học - Ngôn Ngữ, Khoa Học/Tiếng Anh. Mỗi phần thi đều được thiết kế với các dạng câu hỏi phong phú, không chỉ đánh giá kiến thức lý thuyết mà còn kiểm tra khả năng phân tích dữ liệu, xử lý thông tin và vận dụng thực tế. Đây là lựa chọn hoàn hảo cho học sinh muốn tự tin chinh phục kỳ thi đánh giá năng lực.
Câu hỏi liên quan
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions from 29 to 33.
Apples are one of the healthiest foods you can eat every day. A traditional American proverb states: "An apple a day keeps the doctor away". But it does not specifically say anything about the best time of day to eat apples. It is generally believed that eating an apple in the morning is good for people, but eating an apple in the evening is like eating poison.
There is actually a scientific reason behind this belief. One benefit of apples is that they are a favorable source of fructose, which is a natural form of sugar that gives you a big boost of energy. The energy you get from an apple is longer lasting than that provided by a cup of coffee. Clearly, this is something most people would rather experience in the morning than right before bedtime.
Apples also contain high levels of pectin, a kind of dietary fiber. Fiber stimulates bowel movements, which help maintain the health of your digestive system. But if you eat an apple shortly before going to bed, this can cause problems. While you are asleep, your bowels can fill up with gas, making you feel bloated and uncomfortable. You may also wake up several times to use the bathroom, which will prevent you from getting a good night's sleep.
Other health benefits of apples come from flavonoids, beta carotene, and B vitamins. Flavonoids are the material that gives flowers and fruits their bright colors, such as the deep red of apples. When eaten, flavonoids can decrease your risk of heart disease, diabetes, and other illnesses. Meanwhile, beta carotene helps prevent cancer, and B vitamins provide the body with a wide variety of important benefits. Apparently, starting your day with an apple really can keep the doctor away.
Which of the following gives people a big boost of energy?
Phương pháp nào dưới đây là phương pháp nghiên cứu hóa học?
Read the following passage about online dating and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questions from 23 to 30.
Psychologists have found many advantages and disadvantages to online dating. Among the many criticisms aimed at online dating, the most severe concern is its effects on people's self-esteem and mental health.
Swipe left or right is the main feature of popular dating apps, where users quickly look at profiles. However, this system is criticized for being superficial. A study showed that users often feel less satisfied with their appearance. Jessica Strübel found that after a while, users begin to feel less like unique, special individuals and more like they're disposable. This feeling leads to users becoming increasingly sensitive about their looks and bodies, heightening self-consciousness. Dating apps also added to the idea that there's always something better around the corner, which further pressures users into trying to appear more attractive.
Dating apps not only harm self-esteem but also alter perceptions of relationships. By accelerating the dating process, these apps encourage poor social behavior. For instance, it's not unusual for people to ignore "likes" and messages or to lose interest and cut off communication. This behavior would have been considered extremely rude in the past. But with online dating, it is a common reality.
Furthermore, thirty-five percent of users actually reported feeling pessimistic about dating. Only twenty-eight percent of surveyed users reported feeling hopeful after using a dating site or app.
The word profiles in paragraph 2 is CLOSEST in meaning to _____.
Cho hai mệnh đề: \(P\): “\({2^3} \cdot {5^{2025}} \ge {7^{1000}}\)”, \(Q\): “Tổng số đo bốn góc trong một tứ giác bằng \(360^\circ \)”.
a) Mệnh đề phủ định của mệnh đề \(P\) là \(\overline P \): “\({2^3} \cdot {5^{2025}} < {7^{1000}}\)”.
b) Phát biểu mệnh đề \(P \Rightarrow Q\): “Nếu tổng số đo bốn góc trong một tứ giác bằng \(360^\circ \) thì \({2^3} \cdot {5^{2025}} \ge {7^{1000}}\)”.
c) Mệnh đề \(P \Rightarrow Q\) đúng.
d) Phát biểu mệnh đề \(P \Rightarrow Q\) bằng cách sử dụng điều kiện đủ là: “Tổng số đo bốn góc trong một tứ giác bằng \(360^\circ \) là điều kiện đủ để \({2^3} \cdot {5^{2025}} \ge {7^{1000}}\)”.
Cường độ thoát hơi nước được điều chỉnh bởi cơ chế nào?
Ngữ liệu sau mắc lỗi gì?
Văn học là nhân học. Tác phẩm văn học có giá trị phải luôn hướng đến con người.
Read the following passage about the Science in Service of Humanity and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.
Science has come out of its shell in laboratories to become a powerful force for human advancement. Modern scientific endeavors increasingly focus on addressing real-world challenges affecting communities globally. From developing vaccines that save millions to creating technologies connecting people across continents, science serves humanity in countless ways. This shift represents a fundamental evolution in how we perceive scientific progress—not merely academic pursuit but a practical tool for improving lives and solving pressing problems.
[I] Medical breakthroughs exemplify how science directly benefits humanity. [II] For instance, gene therapy offers hope for those with inherited conditions, while artificial intelligence helps diagnose diseases earlier and more accurately. [III] These advancements didn't happen overnight; scientists had to burn the midnight oil for years before achieving success. [IV] Their perseverance demonstrates that when science targets humanitarian goals, results can transform society profoundly.
Environmental science has emerged as another crucial domain where laboratory work translates into human welfare. Climate scientists provide data informing policy decisions affecting billions. Conservation biologists develop strategies to protect biodiversity, ensuring future generations benefit from natural resources. Agricultural researchers create drought-resistant crops helping communities withstand changing climate conditions. Despite these contributions, environmental science faces challenges including funding limitations, political resistance, and urgency of addressing accelerating climate change. Nevertheless, dedicated scientists continue their work, recognizing environmental health directly impacts human wellbeing.
The future of science in service of humanity looks increasingly collaborative and inclusive. Modern approaches incorporate diverse perspectives, including indigenous knowledge and community participation. Citizen science projects engage non-professionals in data collection, democratizing the scientific process. Open-access publishing makes research findings available to anyone with internet access, not just wealthy institutions. These developments suggest science's greatest potential lies in becoming more accessible and responsive to human needs. As we face complex global challenges, from pandemics to climate change, science serving humanity offers our best hope for a sustainable future.
The word “informing” in paragraph 3 is OPPOSITE in meaning to _________.
Mark the letter A, B, C or D on your answer sheet to indicate the best arrangement of utterances or sentences to make a meaningful exchange or text in each of thefollowing questions from 13 to 17.
Hi Josh,
a. I managed to fix the issue with my laptop, thanks to your advice.
b. It was just a small technical glitch, but I wouldn't have figured it out on my own.
c. Now it’s running smoothly, and I can get back to work.
d. By the way, let’s grab coffee sometime next week!
e. I’d love to hear about your latest project.
Best,
Emma
Dân số nước ta đứng thứ bao nhiêu trong khu vực Đông Nam Á?
Cho hai mệnh đề P: “x là số chẵn” và Q: “x chia hết cho 2”.
Phát biểu mệnh đề P kéo theo Q.
CHỦ ĐỀ: GIẢI NOBEL HÓA HỌC 2020
(Tham khảo bài văn của chủ đề trong đường link dưới đây ở trang 21)
https://tvsthpt.dlib.vn/app/doc-sach-ebook/d00ddd794efd
Và trả lời câu hỏi sau:
Ý chính của bài đọc là gì?
Read the following passage about lifelong learning and mark the letter A, B, C, or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.
[I] Lifelong learning is the ongoing, voluntary, and self-motivated pursuit of knowledge for personal or professional development (Knowles, 2020). [II] This concept emphasizes that learning does not stop after formal education, but rather continues throughout an individual's life, adapting to changing circumstances and needs. [III] In today’s fast-paced world, where technology and job markets evolve rapidly, lifelong learning has become increasingly essential. [IV]
One of the primary benefits of lifelong learning is its ability to enhance employability. Individuals who engage in continuous education are more likely to keep their skills relevant and competitive in the job market. According to a report by the World Economic Forum (2021), over 50% of employees will need reskilling due to technological advancements in the coming years. Lifelong learners are better equipped to adapt to these changes, making them more attractive candidates for employers.
Moreover, lifelong learning contributes to personal fulfillment and mental well-being. Engaging in new learning experiences can stimulate the brain, foster creativity, and improve cognitive function. Research indicates that individuals who pursue learning opportunities throughout their lives tend to report higher levels of happiness and life satisfaction (Smith & Johnson, 2019). Whether it is taking a course, learning a new language, or picking up a new hobby, the process of acquiring knowledge can be enriching and enjoyable.
In addition, lifelong learning promotes social engagement and community involvement. Participating in educational programs or community workshops can foster connections with others who share similar interests. This social aspect of learning can enhance one's sense of belonging and support networks, which are crucial for mental health (Jones, 2022).
Overall, lifelong learning is not just an individual responsibility; it requires support from educational institutions, employers, and communities to create an environment conducive to continuous education. By fostering a culture of learning, society can better prepare individuals for the challenges of the future and ensure that everyone has the opportunity to thrive.
(Adapted from The Importance of Lifelong Learning by Knowles, Smith, Johnson, and others)
The word "it" in paragraph 5 refers to ____.
Find the word which has a different sound in the part underlined.
Cơ năng của vật bảo toàn khi vật chịu tác dụng của lực
Trong thời gian liên tục \(25\) năm, một người lao động luôn gửi đúng 4 000 000 đồng vào một ngày cố định của tháng ở ngân hàng \(M\) với lại suất không thay đổi trong suốt thời gian gửi tiền là \(0,6\text{ }\!\!%\!\!\text{ }\) tháng. Gọi \(A\) đồng là số tiền người đó có được sau \(25\) năm. Tính A, đơn vị triệu đồng, làm tròn tới hàng đơn vị.
Một bit được biểu diễn ra sao?
Biết là độ dịch chuyển 3 m về phía đông còn là độ dịch chuyển 4 m về phía bắc. Hãy xác định độ lớn, phương và chiều của độ dịch chuyển tổng hợp
Hoạt động tạo ra sản phẩm vật chất và tinh thần quyết định tạo ra sản phẩm vật chất và tinh thần quyết định sự tồn tại phát triển của con người và xã hội gọi là gì?
Thiết bị nào phía dưới là thiết bị vào?
Đâu không phải là chức năng của giá cả thị trường?