已知f(t)的傅里叶变换为<img src="https://static.zxtiku.com/wangke/imgs/topic/df973486e8e6f828f5e97144f568f257.jpg"/>，f(t)的波形如图所示，则<img src="https://static.zxtiku.com/wangke/imgs/topic/eacfad98a7a36a99597cc46ce803ebf5.jpg"/>=( )。<img src="https://static.zxtiku.com/wangke/imgs/topic/02474ec58cdf28370758ce5e8ab747b9.jpg"/>