y=-x^2+|x|=-x^2±x,开口向下,对称轴x=±1/2当x≤0时：y=-x^2-x,对称轴x=-1/2单调减区间：[-1/2,0]最大值：f(-1/2)=-(-1/2)^2-(-1/2)=-1/4+1/2=1/4当x≥0时：y=-x^2+x,对称轴x=1/2单调减区间：[1/2,+∞）最大值：f(1...