函数y=13sin2xcos2x的最小值和周期分别为A.-2/3,π/2 B.-1/6,π/2 C.1/6,2π D.2/3,4π最好要详细的讲解

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函数y=13sin2xcos2x的最小值和周期分别为A.-2/3,π/2 B.-1/6,π/2 C.1/6,2π D.2/3,4π最好要详细的讲解
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函数y=13sin2xcos2x的最小值和周期分别为A.-2/3,π/2 B.-1/6,π/2 C.1/6,2π D.2/3,4π最好要详细的讲解
函数y=13sin2xcos2x的最小值和周期分别为
A.-2/3,π/2
B.-1/6,π/2
C.1/6,2π
D.2/3,4π
最好要详细的讲解

函数y=13sin2xcos2x的最小值和周期分别为A.-2/3,π/2 B.-1/6,π/2 C.1/6,2π D.2/3,4π最好要详细的讲解
y=1/3sin2xcos2x才对
sin2xcos2x=(sin4x)/2
sin4x>=-1
所以最小值1/3*(1/2)*(-1)=-1/6
sin4x的周期为2pi/4=pi/2 选B