问题标题：
sin(30°+α)×tan(135°+α)×tan(135°-α)1/cos(60°-α)
问题描述：
sin(30°+α)×tan(135°+α)×tan(135°-α)1/cos(60°-α)
陆涛栋回答：
sin(30°+α)×tan(135°+α)×tan(135°-α)1/cos(60°-α)=sin(30°+α)×tan(90°+45°+α)×tan(180°-(45°+α))1/cos(90°-(30°+α))=sin(30°+α)×[-cot(45°+α)]×[-tan((45°+α))]1/sin(30°+α)=1
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