Cho hàm số f(x) xác định trên R và có đồ thị hàm s...
Câu hỏi: Cho hàm số f(x) xác định trên R và có đồ thị hàm số f’(x) như hình vẽ. Hàm số f(x) có mấy điểm cực trị ?![](data:image/png;base64,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)
A 1
B 2
C 3
D 4
Câu hỏi trên thuộc đề trắc nghiệm
Đề thi thử THPT QG môn Toán trường THPT Chuyên Thái Nguyên - lần 2 - năm 2017 ( có lời giải chi tiết)