Sin6sin42sin66sin78
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发布时间:2022-05-04 17:22
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热心网友
时间:2022-06-24 08:27
Sin6sin42sin66sin78
=Sin6*cos12*cos24*cos48
=2cos6*Sin6*cos12*cos24*cos48/2cos6
=sin12*cos12*cos24*cos48/2cos6
=2sin12*cos12*cos24*cos48/4cos6
=sin24*cos24*cos48/4cos6
=2sin24*cos24*cos48/8cos6
=sin48**cos48/8cos6
=2sin48**cos48/16cos6
=sin96/16cos6
=cos6/16cos6
=1/16
热心网友
时间:2022-06-24 08:27
这题以前做过原式=sin6cos48cos24cos12 =sin6cos48cos24sin24/2sin12 =sin6cos48sin48/4sin12 =sin6sin96/8sin12 =sin6cos6/8sin12 =sin12/16sin12