高一数学解答 !急!三角函数sin25π/12·cos11π/6-cos11π/12·sin5π/6

网友回答

（sin25π/12*cos11π/6)-(cos11π/12*sin5π6)
=（sinπ/12*cosπ/6)-(-cosπ/12*sinπ/6)
=sinπ/12*cosπ/6+cosπ/12*sinπ/6
=sin(π/12+π/6)
=sin(π/4)
=√2/2答案是B啊啊啊,======以下答案可供参考======
供参考答案1:
根据三角函数以及角度换算之间的关系，选 B.
供参考答案2:
sin25π/12·cos11π/6-cos11π/12·sin5π/6
=-sinπ/12·cos5π/6+cosπ/12·sin5π/6
=sin（5π/6-π/12)
=sin3π/4
=√2/2选B供参考答案3:
sin25π/12·cos11π/6-cos11π/12·sin5π/6
=sinπ/12·cosπ/6+cosπ/12·sinπ/6
=sin（π/6+π/12)
=sinπ/4
=√2/2选B供参考答案4:
B原式=sinπ/12·cosπ/6+cosπ/12·sinπ/6
=sin（π/12+π/6）=sin（π/4）=√2/2