Chọn đáp án C.
Câu hỏi trên thuộc đề trắc nghiệm dưới đây !
Số câu hỏi: 1000
Tập nghiệm của bất phương trình log2x>3 là
A.4 ; +∞ .
B.6 ; +∞ .
C.9 ; +∞ .
D.8 ; +∞ .
Đáp án và lời giải
Đáp án:D
Lời giải:Lời giải
Ta có: log2x>3⇔x>0x>23⇔x>8 .
Vậy tập nghiệm của bất phương trình là S=8;+∞ .
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