已知5sin(α+β)+3sinα=0.求tan[α+(β/2)]cotβ/2的值.

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已知5sin(α+β)+3sinα=0.求tan[α+(β/2)]cotβ/2的值.
已知5sin(α+β)+3sinα=0.求tan[α+(β/2)]cotβ/2的值.

已知5sin(α+β)+3sinα=0.求tan[α+(β/2)]cotβ/2的值.
because:
5sin(a+b)+3sina=5sin(a+b/2)cos(b/2)+5sin(b/2)cos(a+b/2)+3sin(a+b/2)cos(b/2)-3sin(b/2)cos(a+b/2)=0
so:8sin(a+b/2)cos(b/2) =-2sin(b/2)cos(a+b/2)
so:tan(a+b/2)cos(b/2)=-1/4(左除以右)