Cho hàm số \(f(x)=x^{3}-m x^{2}-m^{2} x+8(*)\), với \(m\) là tham số thực.
Với \(m=2\), giá trị nhỏ nhất của hàm số \(y=f(x)\) trên đoạn \([-1 ; 3]\) là:
Hãy suy nghĩ và trả lời câu hỏi trước khi xem đáp án
Khi \(m=2\), ta có phương trình \((*)\) trở thành \(f(x)=x^{3}-2 x^{2}-4 x+8\)
Ta có \(f^{\prime}(x)=3 x^{2}-4 x-4=0 \Leftrightarrow\left[\begin{array}{l}x=2 \\ x=-\frac{2}{3}\end{array}\right.\)
Ta xét \(\left\{\begin{array}{l}f(-1)=9 \\ f\left(-\frac{2}{3}\right)=\frac{256}{27} \\ f(2)=0 \\ f(3)=5\end{array}\right.\)
Vậy giá trị nhỏ nhất của hàm số trên đoạn \([-1 ; 3]\) là \(f(2)=0\).
Câu hỏi liên quan
Ở trạng thái cơ bản cấu hình electron nguyên tử nào sau đây là của phi kim?
Hóa học có vai trò quan trọng trong
Trong không gian Oxyz, cho \(A(1;2;-3),B(3;-5;2)\). Tọa độ vectơ \(\overrightarrow{AB}\) là
Chọn phương án ghép đúng nói về thuật ngữ tin học trong các câu sau: Tin học là…
Read the following leaflet and mark the letter A, B, C or D on your answer sheet to indicate the option that best fits each of the numbered blanks from 7 to 12.
TO STAY HEALTHY, BEGIN AT HOME!
Let’s look at what we can do each day to improve our health and well-being.
Facts and Figures:
Over 30% of adults do not get enough physical activity, and (7)_______ spend hours sitting in front of screens, which affects both their physical and mental health.
Positive Actions!
(8)________ your intake of sugary or salty processed foods and opt for healthier alternatives like fruits or nuts.
Focus on (9)________ fresh, nutrient-rich foods rather than heavily processed ones. This not only nourishes your body but also helps the environment by reducing (10)________.
(11)_________ how busy your schedule is, dedicate at least 30 minutes a day to physical activity. Consistency is key!
Start Today!
Small changes can lead to big (12)_______. Make the choice to live a healthier, happier life!
Hai quả cầu dẫn điện giống hệt nhau được tích điện +2Q và −Q tương ứng và cách nhau một khoảng d (lớn hơn nhiều so với bán kính của các hình cầu) như hình trên. Độ lớn lực hấp dẫn lên quả cầu bên trái là F1. Sau khi cho hai quả cầu chạm nhau rồi lại cách nhau một khoảng d thì độ lớn của lực tác dụng lên quả cầu bên trái là F2. Mối quan hệ nào sau đây là đúng?
Read the following passage about studying abroad 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.
Successful students often do the followings while studying. First, they have an overview before reading. Next, they look for important information and pay greater attention to it (which often needs jumping forward or backward to process information). They also relate important points to one another. Also, they activate and use their prior knowledge. When they realize that their understanding is not good, they do not wait to change strategies. Last, they can monitor understanding and take action to correct or “fix up” mistakes in comprehension.
Conversely, students with low academic achievement often demonstrate ineffective study skills. [I] They tend to assume a passive role in learning and rely on others (e.g., teachers, parents) to monitor their studying. [II] For example, low-achieving students often do not monitor their understanding of content; they may not be aware of the purpose of studying; and they show little evidence of looking back or employing “fix-up” strategies to fix understanding problems. [III] Students who struggle with learning new information seem to be unaware that they must extend effort beyond simply reading the content to understand and remember it. [IV]
Children with learning disabilities do not plan and judge the quality of their studying. Their studying may be disorganized. Students with learning problems face challenges with personal organization as well. They often have difficulty keeping track of materials and assignments, following directions, and completing work on time. Unlike good studiers who employ a variety of study skills in a flexible yet purposeful manner, low-achieving students use a restricted range of study skills. They cannot explain why good study strategies are important for learning; and they tend to use the same, often ineffective study approach for all learning tasks, ignoring task content, structure or difficulty.
Where in paragraph 2 does the following sentence best fit?
This lack of initiative often leads to poor comprehension and retention of information.
Vi sinh vật quang tự dưỡng cần nguồn năng lượng và nguồn cacbon chủ yếu từ đâu?
Câu nào sau đây không đúng về bước úm gà con trong quy trình nuôi gà thịt công nghiệp?
Choose the word(s) CLOSEST in meaning to the underlined word(s).
We were pretty disappointed with the quality of the food.Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer questions.
Parents of a Tokyo elementary school are up in arms at being asked to pay 730 dollars for their child's school uniform. A public elementary school in Tokyo's upmarket Ginza district has decided to adopt new school uniforms designed by the luxury Italian designer Armani. The bespoke uniforms, which include a hat and bag, are priced at over 80,000 (730 dollars) each. Parents are angry at the school's decision and are protesting at what they view as the exorbitant price for a uniform of an eight-year-old chilThe school said it wanted a designer uniform that represented the rich area of GinzSchool officials visited top department stores and decided to ask the fashion brand Armani to design the uniform.
The expensive uniform has created such a fuss that it has been discussed in Japan's parliament. One lawmaker said that since the school is public and not private, "a certain price range needs to be considered". Finance Minister Taro Aso sai"Clearly it's expensive. It would be tough if a student could not afford to pay for it." Japan's education minister said steps would be taken to ensure the financial burden placed on parents for uniforms, "would not be excessive". Twitter users said young children are not interested in designer clothes. The school principal sai"With humility, I take the criticism that the explanation has been insufficient and not well-timeI will go on explaining carefully to those concerned."
(Source: https.//www.japantimes.co.jp/news/2018/02/09/national/armani-parents-question-pricey-uniforms-public-school-tokyos-ginza-district/)
Which of the following is closest in meaning to “up in arms” as used in the passage?
Nguyên nhân nào làm cho kinh tế nhiều quốc gia Mĩ La tinh đang từng bước được cải thiện chủ yếu?
Đâu là ý đúng: Nguyên tắc đầu tiên khi bón phân hóa học là gì?
Con đường lây bệnh tai xanh ở lợn là
Loại thuốc thử nào được dùng để nhận biết sự có mặt của glucose trong tế bào?
Nêu những ứng dụng của chất phóng xạ trong đời sống?
Trên hình chiếu phối cảnh, đường chân trời là:
Mark the letter A, B, C or D on your answer sheet to indicate the correct option that best fits each of the numbered blanks from 22 to 26.
WAYS TO IMPROVE YOUR MEMORY
A good memory is often seen as something that comes naturally, and a bad memory as something that cannot be changed, but actually (22) ____________ to improve your memory.
We all remember the things we are interested in and forget the ones that bore us. This no doubt explains the reason why schoolboys remember football results (23) __________ but struggle with dates from their history lessons! Take an active interest in what you want to remember, and (24) ____________ . One way to make yourself more interested is to ask questions — the more the better!
Physical exercise is also important for your memory, because it increases (25) _______________ and sends more oxygen to your brain, and that makes your memory work better. Exercise also reduces stress, (26) _________________.
The old saying that ― eating fish makes you brainy may be true after all. Scientists have discovered that the fats found in fish like tuna, sardines and salmon — as well as in olive oil — help to improve the memory. Vitamin-rich fruits such as oranges, strawberries and red grapes are all good brain food, too.
Lực nào sau đây có thể là lực hướng tâm
Để viết 3 mũ 4 trong Python chọn