y=log1/2[sin（1/2 x+π/3）]底1/2＜1∴当真数sin（1/2 x+π/3）＞0并且单调减时,y单调增∴2kπ+π/2 ≤ 1/2 x+π/3 ＜2kπ+π4kπ+π ≤ x+2π/3 ＜4kπ+2π4kπ+π/3 ≤ x+2π/3 ＜4kπ+4π/3y=log1/2[sin（1/2x+...