函数y=sinx+cosx的最小值和最小正周期分别是 ( )
A:-2,2π
B:-2,2π
C:-2,π
D:-2,π
在△ABC中,∠C为锐角,分别以AB,AC为直径作半圆,过点B,A,C作,如图所示.若AB=4,AC=2,S1﹣S2=π4,则S3﹣S4的值是( )
They are going to take some .( )
Tom and Jenny are in the same school. And _________ like sports very much.