赞 梦想在望 幼苗
共回答了22个问题采纳率：90.9% 举报
=[1/(sin π/15)]*sinπ/15 *cos π/15 * cos 2π/15 * cos4π/15 * cos8π/15
=[1/(sin π/15)]*(1/2)*sin2π/15 * cos 2π/15 * cos4π/15 * cos8π/15
=[1/(sin π/15)]*(1/4)*sin4π/15 * cos4π/15 * cos8π/15
=[1/(sin π/15)]*(1/8)*sin8π/15 * cos8π/15
=[1/(sin π/15)]*(1/16)*sin16π/15
=[1/(sin π/15)]*(1/16)*sin(π+π/15 )
=[1/(sin π/15)]*(1/16)*sinπ/15
=1/16
=[1/(sin π/15)]*(1/2)*sin2π/15 * cos 2π/15 * cos4π/15 * cos8π/15
=[1/(sin π/15)]*(1/4)*sin4π/15 * cos4π/15 * cos8π/15
=[1/(sin π/15)]*(1/8)*sin8π/15 * cos8π/15
=[1/(sin π/15)]*(1/16)*sin16π/15
=[1/(sin π/15)]*(1/16)*sin(π+π/15 )
=[1/(sin π/15)]*(1/16)*sinπ/15
=1/16
1年前
10
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你能帮帮他们吗