cos二倍角公式的推导
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发布时间:2022-04-28 13:09
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热心网友
时间:2023-10-09 21:04
Cos2α=cos(α+α)
=cosαcosα-sinαsinα
=cos^2α-sin^2α
=1-sin^2α-sin^2α
=1-2Sinα^2
Cos2α=cos(α+α)
=cosαcosα-sinαsinα
=cos^2α-sin^2α
=cos^2α-(1-cos^2α)
=2cos^2α-1
热心网友
时间:2023-10-09 21:04
Cos2α=cos(α+α)
=cosαcosα-sinαsinα
=cos^2α-sin^2α
=1-sin^2α-sin^2α
=1-2Sinα^2
Cos2α=cos(α+α)
=cosαcosα-sinαsinα
=cos^2α-sin^2α
=cos^2α-(1-cos^2α)
=2cos^2α-1