Phương trình ${{2}^{{{x}^{2}}+3x}}=1$ có nghiệm

Cho hàm số $y=f(x)$ có bảng xét dấu của đạo hàm như sau:

Hàm số đã cho nghịch biến trên khoảng nào dưới đây?

Read the following passage about endangered languages and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questionsfrom 31 to 40.

[I] Social media has become a dominant force in modern communication, offering a range of benefits and challenges. [II] It has revolutionized the way people interact, share information, and even form relationships. [III] While these platforms offer opportunities for connection and expression, they also have their drawbacks. [IV] For instance, excessive use of social media has been linked to a range of negative effects, including mental health issues, social isolation, and decreased productivity. [V] However, when used responsibly, social media can also offer a variety of positive outcomes, such as the ability to stay connected with loved ones, network professionally, and access valuable information and resources.

One of the major benefits of social media is its ability to keep people connected. For example, individuals who live far apart can maintain close relationships through regular communication on these platforms. Social media also facilitates professional networking, allowing users to connect with potential employers or clients, and enabling companies to promote their products and services to a global audience. Additionally, platforms like Facebook, Twitter, and Instagram provide a space for people to share ideas, opinions, and creative work, fostering a sense of community and collaboration.

Despite these advantages, there are serious concerns about the negative impact of social media, particularly on mental health. Studies have shown that excessive social media use can contribute to feelings of anxiety, depression, and loneliness. This is often attributed to the unrealistic portrayals of life that are commonly shared on these platforms, leading to comparisons that can make individuals feel inadequate or left out. Furthermore, constant exposure to negative news or online bullying can exacerbate these feelings and contribute to long-term psychological stress.

Another issue with social media is its potential to distract people from their daily responsibilities. With notifications constantly popping up and endless streams of content to scroll through, individuals may find it difficult to focus on tasks such as work, school, or personal obligations. This can result in decreased productivity and a lack of attention to important matters.

Ultimately, the impact of social media depends on how it is used. If individuals are mindful of their usage patterns and take steps to limit their time on these platforms, they can enjoy the benefits of staying connected and informed without the negative consequences. Parents, educators, and mental health professionals can also play a role in helping young people develop healthy habits and manage their social media use effectively.

Which of the following best paraphrases the underlined sentence in paragraph 1?

“Social media has become a dominant force in modern communication."

Ở ven biển của Cộng hòa Nam Phi có dãy núi nào?

Sau Chiến tranh thế giới thứ hai, sự mở rộng của chủ nghĩa xã hội ở châu Á gắn liền với những quốc gia nào sau đây?

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 the following questions from 13 to 17.

a.    Tom: Yes, it is. The bus should be here in five minutes. Are you new to town?

b.    Sarah: I am! Just moved here last week. I'm looking for a good coffee shop near the park.

c.    Sarah: Good morning! Is this the right bus stop for the city center?

Hai bạn An và Bình kéo nước từ giếng lên. An kéo gàu nước nặng gấp đôi, thời gian kéo gàu nước lên của Bình chỉ bằng một nửa thời gian của An. Phát biểu nào là đúng khi so sánh công suất trung bình của An và Bình?

Cho tam giác ABC nội tiếp đường tròn bán kính R,  AB = R, $AC=R\sqrt{2}.$ Tính số đo của $\hat{A}$ biết $\hat{A}$ là góc tù?

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence(s) that best complete(s) each of the following exchanges.

Greg: “Kate, Giga Mall is having a big sale this week. You wanna go?”

Kate: “_____________”

Mark the letter A, B, C or D to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions.

Read the following advertisement 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 1 to 6.

"Welcome to FitLife Gym, the newest fitness center in town! We take pride in offering you a modern space equipped with state-of-the-art equipment and a team of expert trainers (1)______ to helping you achieve your fitness goals. At FitLife, we provide a variety of programs designed (2)______  all fitness levels, from beginners to advanced athletes.

Not only do we feature cardio and strength training areas, but we also offer yoga, pilates, and engaging group classes (3)______you motivated. With (4)______ you can easily choose the right plan that fits your schedule and lifestyle. At FitLife Gym, you'll experience the support of our dedicated team in a friendly and encouraging (5)______ . Join us today to kickstart your health journey and discover the difference that a supportive community can (6)______a difference in reaching your fitness aspirations!"

Để kiểm tra giả thuyết "Nếu đặt chậu cây ở một nơi bất kì thì thân cây sẽ phát triển cong về phía có ánh sáng", người ta tiến hành thí nghiệm trồng hai chậu cây cùng loài ở hai vị trí khác nhau (gần cửa sổ, góc cầu thang). Hoạt động này thuộc bước nào trong tiến trình nghiên cứu môn Sinh học?