y=2根号3 sinxcosx+cos2x=2sin(2x+π/6) 最小正周期T=π单调递增区间2kπ-π/2≤2x+π/6≤2kπ+π/2 ,2kπ-2π/3≤2x≤2kπ+π/3kπ-π/3≤x≤kπ+π/6y=2sinx(x∈R) 图象纵坐标不变,横坐标变为原来的1/2倍得函数y=2...求对称轴方程