Gaokao Math Practice Question
8. 下列函数中最小值为 4 的是（ ）
- A.$y=x^{2}+2 x+4$
- B.$y=|\sin x|+\frac{4}{|\sin x|}$
- C.$y=2^{x}+2^{2-x}$
- D.$y=\ln x+\frac{4}{\ln x}$
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