14,(1),ω=2,T=2π/ω=π; (kπ-3π/8 (kπ+π/8(2),-π/4≤x≤π/4,∴-π/4≤2x+π/4≤3π/4,∴-√2/2≤sin(2x+π/4)≤√2/2∴-1≤√2sin(2x+π/4)≤1故最小值为-1,最大值为1.