y=cos2x+根号下3*sin2x=2sin(2x+π/6)值域[-2,2]2kπ-π/2≤2x+π/6≤2kπ+π/2,k∈Z解出x得单增区间2kπ+π/2≤2x+π/6≤2kπ+3π/2,k∈Z解出x得单减区间2x+π/6= kπ+π/2,k∈Z解出x得对称轴方程百度一下：ok吧_博...