Nhà Văn hóa Thanh niên của thành phố X muốn trang...
Câu hỏi: Nhà Văn hóa Thanh niên của thành phố X muốn trang trí đèn dây led gần cổng. Ban giám đốc Nhà Văn hóa Thanh niên chỉ cho nhà thiết kế biết chỗ chuẩn bị trang trí đã có hai trụ đèn cao áp mạ kẽm đặt cố định ở vị trí A và B có độ cao lần lượt là 10m và 30m khoảng cách giữa hai trụ đèn 24m và cũng yêu cầu nhà thiết kế chọn một cái chốt ở vị trí M trên mặt đất nằm giữa hai chân trụ đèn để giăng đèn dây Led nối đến hai đỉnh C và D của trụ đèn (như hình vẽ). Hỏi nhà thiết kế phải đặt chốt ở vị trí cách trụ đèn B trên mặt đất là bao nhiêu để tổng độ dài của hai sợi dây đèn led ngắn nhất 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)
A. 20m
B. 6m
C. 18m
D. 12m
Câu hỏi trên thuộc đề trắc nghiệm
Đề trắc nghiệm ôn thi học kì 1 môn Toán lớp 12 năm 2018 - 2019 có lời giải - Đề số 5