已知sin(a+135°)=5/13,cos(45°-β ),且-45°cos(45°-β )=3/5
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/30 21:57:12
![已知sin(a+135°)=5/13,cos(45°-β ),且-45°cos(45°-β )=3/5](/uploads/image/z/3754778-50-8.jpg?t=%E5%B7%B2%E7%9F%A5sin%28a%2B135%C2%B0%29%3D5%2F13%2Ccos%2845%C2%B0-%CE%B2+%29%2C%E4%B8%94-45%C2%B0cos%2845%C2%B0-%CE%B2+%29%3D3%2F5)
已知sin(a+135°)=5/13,cos(45°-β ),且-45°cos(45°-β )=3/5
已知sin(a+135°)=5/13,cos(45°-β ),且-45°
cos(45°-β )=3/5
已知sin(a+135°)=5/13,cos(45°-β ),且-45°cos(45°-β )=3/5
cos2(a-β)=2cos^2(a-β)-1
-45°