Question

若角α的终边和函数y=-|x|的图像重合,试写出角α的集合

Answer 1

y>0=>y=-x=>α=2kπ+7/4π

y>0=>y=-x=>α=2kπ+5/4π

{x|x=2kπ+7/4π或2kπ+5/4π}