Cho hàm số \(y=f(x)\), liên tục trên R và có bảng...
Câu hỏi: Cho hàm số \(y=f(x)\), liên tục trên R và có bảng biến thiên như hình vẽ bên. Tìm số nghiệm thực của phương trình \(2f\left( x \right) + 7 = 0\) 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)
A. 1
B. 3
C. 4
D. 2
Câu hỏi trên thuộc đề trắc nghiệm
Đề thi thử THPT QG năm 2019 môn Toán Trường THPT Chuyên Lam Sơn - Thanh Hóa lần 2