已知向量a=(cos3x/2,sin3x/2),向量b=(cosx/2,-sinx/2),x∈[-π/3,π/2],若|a+b|=1/3,求cosx的值.
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/10 15:44:26
![已知向量a=(cos3x/2,sin3x/2),向量b=(cosx/2,-sinx/2),x∈[-π/3,π/2],若|a+b|=1/3,求cosx的值.](/uploads/image/z/193364-44-4.jpg?t=%E5%B7%B2%E7%9F%A5%E5%90%91%E9%87%8Fa%3D%28cos3x%2F2%2Csin3x%2F2%29%2C%E5%90%91%E9%87%8Fb%3D%28cosx%2F2%2C-sinx%2F2%29%2Cx%E2%88%88%5B-%CF%80%2F3%2C%CF%80%2F2%5D%2C%E8%8B%A5%7Ca%2Bb%7C%3D1%2F3%2C%E6%B1%82cosx%E7%9A%84%E5%80%BC.)
xUjPB-BIZ]ux#H
"mLJВRمA"Rs9.F93su̽~_?{znЊ]]Z"=` 8MCO@Qc3ڽWq>I{kUr)j^V0S3/Hfm-(6SFZQmiMEaYMLxuA]@K4@6
)ݕ&=| -$;^-X*MTo+V6ovm.0+0>HJa2jx.]ylz
- P1lR:f9(pf/[g$T0$U|B