问题
填空题
sin71ocos26o-sin19osin26o的值为 ______.
答案
∵sin71ocos26o-sin19osin26=cos19°cos26°-sin19°sin26°
=cos(19°+26°)=cos45°=2 2
故答案为:2 2
sin71ocos26o-sin19osin26o的值为 ______.
∵sin71ocos26o-sin19osin26=cos19°cos26°-sin19°sin26°
=cos(19°+26°)=cos45°=2 2
故答案为:2 2