求y=cos(2x-π/4)的单调递增区间解：y=cosx的单调递增区间：[2kπ-π，2kπ]，k∈Z∴2kπ-π≤2x-π/4≤2kπ+0，k∈Z2kπ-π+π/4≤2x≤2kπ+π/42kπ+3π/4≤2x≤2kπ+π/4kπ+3π/8≤x≤kπ+π/8y=cos(2x-π/4)的单调递增区间：[kπ+3π/8，kπ+π/8](k∈Z)
