π/4-2x=2kπ+π/2取得最大值1+√2π/4-2x=2kπ-π/2取得最大值1-√2x自己解出来f(x)=√2sin(π/4-2x)+1=-√2sin(2x-π/4)+1增区间,解一下2x-π/4∈（2kπ+π/2,2kπ+3π/2）减区间,解一下2x-π/4∈（2kπ-π/2,2kπ...