求答案和解析(2问图也要)

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/04 16:36:36
求答案和解析(2问图也要)

求答案和解析(2问图也要)
求答案和解析(2问图也要)

求答案和解析(2问图也要)

f(x)=sinx+√3cosx

    =2(1/2*sinx+√3/2*cosx)

    =2(sinxcosπ/3+cosxsinπ/3)

    2sin(x+π/3)

(1)

周期是k*2π=2kπ,k∈Z,此问是周期不是最小正周期

振幅=2

(2)

令x+π/3=0,π/2,π,3π/2,2π

x=-π/3,π/6,2π/3,7π/6,5π/3

画出点(-π/3,0),(π/6,2),(2π/3,0),(7π/6,-2),(5π/3,0)

如图

(3)

∵sinX的减区间是【π/2+2kπ,3π/2+2kπ】,k∈Z

∴令π/2+2kπ<=x+π/3<=3π/2+2kπ,k∈Z

π/6+2kπ<=x<=7π/6+2kπ,k∈Z

f(x)减区间是[π/6+2kπ,7π/6+2kπ],k∈Z


如果您认可我的回答,请点击“采纳为满意答案”,祝学习进步!