Cho dãy số có các số hạng đầu là: \(\frac{1}{4};\frac{1}{{{4^2}}};\frac{1}{{{4^3}}};\frac{1}{{{4^4}}};\frac{1}{{{4^5}}};...\) Số hạng tổng quát của dãy số này là?
\({u_n} = \frac{1}{{{4^{n + 2}}}}\)
\({u_n} = \frac{1}{{{4^{n + 1}}}}\)
\({u_n} = \frac{1}{{{4^n}}}\)
\({u_n} = \frac{1}{{{4^{n - 1}}}}\)
Hãy suy nghĩ và trả lời câu hỏi trước khi xem đáp án
\({u_1} = \frac{1}{{{4^1}}};{u_2} = \frac{1}{{{4^2}}};{u_3} = \frac{1}{{{4^3}}};{u_4} = \frac{1}{{{4^4}}};{u_5} = \frac{1}{{{4^5}}};...\) nên ta dự đoán số hạng tổng quát của dãy số là \({u_n} = \frac{1}{{{4^n}}}\)
Đáp án C
Bộ Đề Kiểm Tra Giữa Học Kì I - Toán 11 - (Năm học 2023 - 2024) - Các Trường THPT Trên Toàn Quốc cung cấp các câu hỏi trắc nghiệm giúp học sinh ôn tập và củng cố kiến thức đã học. Tài liệu bao gồm các bài tập từ cơ bản đến nâng cao, giúp học sinh rèn luyện kỹ năng phân tích và áp dụng kiến thức đã học vào thực tế.
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Văn bản quy phạm pháp luật bao gồm mấy loại chính?
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Nguyên nhân chủ yếu nào đã làm cho tốc độ phát triển kinh tế không đều, đầu tư nước ngoài giảm mạnh ở Mỹ Latinh?
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Đặc điểm nào là đúng khi nói về con đường hấp thụ nước và ion khoáng qua thành tế bào – gian bào ở rễ cây?
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