2011 National Question 2 Single-choice Differentiating 2011_老新课标卷 (2011·理) 2.(5分)下列函数中,既是偶函数又在 $(0,+\infty)$ 上单调递增的函数是 ) A. $y=2 x^{3}$B. $y=|x|+1$C. $y=-x^{2}+4$D. $y=2^{-|x|}$ Answer keyB ☆ SaveCan't do it, show the explanation查看原卷 →