求函数y=3sin(2x+兀/4) [0,兀]的单调递减区间.

问题描述:

求函数y=3sin(2x+兀/4) [0,兀]的单调递减区间.

2x+兀/4=[兀/2+2k兀,3兀/2+2k兀]
2x=[兀/4+2k兀,5兀/4+2k兀]
x=[兀/8+k兀,5兀/8+k兀]