Do you ever practice playing the piano in your mind by tapping on imaginary black and white keys when you have no piano in front of you? It’s not unusual--great pianists like Polish-American Arthu
_______ which way to take, the little boy behaved like a real gentleman who comforted his sister from time to time. A. Leaving to wonder B. Having left to wonder C. Left wondering D. L
的最小正周期和最小值，并写出该函数在区间
上的单调递增区间。
