已知函数f（x）＝2cos²x-2coxsinx+1f(x)=2cos²x-2cosxsinx+1=cos2x-sin2x+2=(√2)cos(2x+π/4)+2(1)f(x)max=f(-π/8)=2+√2(2) -π+2kπ≤2x+π/4≤2kπ,单增区间：[-5π/8+kπ,kπ-π/8] (k∈Z)...