(1-cosx)/sinx 还能再怎么化简

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(1-cosx)/sinx 还能再怎么化简
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(1-cosx)/sinx 还能再怎么化简
(1-cosx)/sinx 还能再怎么化简

(1-cosx)/sinx 还能再怎么化简
(1-cosx)/sinx
=sinx(1-cosx)/sin²x
=sinx(1-cosx)/(1-cos²x)
=sinx(1-cosx)/(1+cosx)(1-cosx)
=sinx/(1+cosx)
=2sin(x/2)cos(x/2)/2cos²(x/2)
=sin(x/2)/cos(x/2)
=tan(x/2)

(1-cosx)/sinx =[1-(1-2·cosx/2^2)]/(2·sinx/2·cosx/2)=2·cosx/2^2/(2·sinx/2·cosx/2)=cosx/2/sinx/2=ctgx/2

=tan(x/2)

利用二倍角公式(1-cosx)/sinx=(1-(1-2(sinx/2)^2))/2(sinx/2)(cosx/2)=tanx/2

1-(1-2sinx的平方))/2sinxcosx=2sinx的平方/2sinxcosx=sinx/cosx=tanx
注:我这里的X是你原题上X的一半,也就是半角

tanx/2

把sinx转换成cosx吧