下列函数中,最小正周期为π的函数是A.y=-sinx/3B.y=cosx/2C.y=tanx/4D.y=cos2x

Question

下列函数中,最小正周期为π的函数是
A.y=-sinx/3
B.y=cosx/2
C.y=tanx/4
D.y=cos2x

Answer 1

D
把函数后的表达式看作一个整体,再解出x
A,0<=x/3<=2π ,0<=x<=6π
B,0<=x/2<=2π,0<=x<=4π
C
D.0<=2x<=2π,0<=x<=π