两个初相相等的波源，分别由AB两点向C点无衰减的传播，波长为，AC=/，BC=，则C点的振动一定TwowavesourceswiththesameinitialphasepropagatefromABtwopointstoCpointwithoutattenuation.Thewavelengthis，AC=/，BC=，thenthevibrationofpointCiscertain