已知sin(a-派⼀4)=1⼀3.则cos(a+派⼀4)的值是,急急

2025-04-24 08:55:38
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回答1:

已知sin(a-派/4)=1/3.则cos(a+派/4)
=cos(a-π/4+π/2)
=-sin(a-π/4)=-1/3