• 定义在R上的函数f(x)满足f(x)=f(x+2),当x∈[1,3]时,f(x)=2-|x-2|,则( )试题及答案-单选题-云返教育

    • 试题详情

      定义在R上的函数f(x)满足f(x)=f(x+2),当x∈[1,3]时,f(x)=2-|x-2|,则(  )

      试题解答


      B
      解:由f(x)=f(x+2),∴函数f(x)的周期为2.
      当x∈[1,3]时,f(x)=2-|x-2|,则函数f(x)关于x=2对称.

      A.f(sin
      π
      3
      )=f(
      3
      2
      ),f(sin
      π
      6
      )=f(
      1
      2
      ),此时.f(sin
      π
      3
      )<f(sin
      π
      6
      ),A错误.
      B.f(sin
      3
      )=f(
      3
      2
      ),f(cos
      3
      )=f(-
      1
      2
      )=f(
      1
      2
      ),此时f(sin
      3
      )<f(cos
      3
      ),∴B正确.
      C.f(cos
      π
      3
      )=f(
      1
      2
      ),f(cos
      π
      4
      )=f(
      2
      2
      ),∴f(cos
      π
      3
      )>f(cos
      π
      4
      ),∴C错误.
      D.f(tan
      π
      6
      )=f(
      3
      3
      ),f(tan
      π
      4
      )=f(1),∴f(tan
      π
      6
      )>f(tan
      π
      4
      )∴D错误.
      故选:B.
    MBTS ©2010-2016 edu.why8.cn