Cho hàm số \(y = a{x^2} + bx + c\) có đồ thị như h...
Câu hỏi: Cho hàm số \(y = a{x^2} + bx + c\) có đồ thị như hình dưới đây. Mệnh đề nào sau đây đúng?![](data:image/png;base64,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)
A \(a > 0,\,\,\,b = 0,\,\,c > 0\)
B \(a > 0,\,\,b < 0,\,\,\,c > 0\)
C \(a > 0,\,\,b > 0,\,\,c > 0\)
D \(a < 0,\,\,\,b > 0,\,\,\,c > 0\)
Câu hỏi trên thuộc đề trắc nghiệm
Đề online: Luyện tập hàm số bậc hai - Có lời giải chi tiết