(1)、令a1=sinα α∈(π/3,π/2)
a2=sinα*cos(π/3)+sin(π/3)*|cosα|
=sin(α+π/3)
a3=sin(α+π/3)*cos(π/3)+sin(π/3)*|cos(α+π/3)|
α∈(π/3,π/2),则 α+π/3∈(2π/3,7π/6)
cos(α+π/3)
下面一道有趣的数列大题,大家有空看下吧：
(1)、令a1=sinα α∈(π/3,π/2)
a2=sinα*cos(π/3)+sin(π/3)*|cosα|
=sin(α+π/3)
a3=sin(α+π/3)*cos(π/3)+sin(π/3)*|cos(α+π/3)|
α∈(π/3,π/2),则 α+π/3∈(2π/3,7π/6)
cos(α+π/3)