高校问答下载五粮液防伪查询:高一函数
来源：百度文库 编辑：高校问答 时间：2024/05/07 10:53:48
已知F1,F2分别表示下面两个函数:f1=sin(π/3t+π/4),f2=√3sin(π/3t-π/4),求复合函数f1+f2的振幅,周期,频率及初相
f1=sin(π/3t+π/4),
f2=√3sin(π/3t-π/4) =√3sin(π/3t+π/4-π/2)
=-√3cos(π/3t+π/4)
f1+f2=sin(π/3t+π/4)-√3cos(π/3t+π/4)
=2sin((π/3t+π/4)-π/3)
=2sin(π/3t-π/12)
=2sin(π/3t+23π/12)
故振幅是2，周期是6，初相是23π/12，频率是1/6