在三角形ABC中,角A,B,C所对的边分别是a,b,c,已知向量m=(cosB,-cosA),向量n=(2c+b,a)且向量m∥向量n(1)求sinB+sinC的取值范围(2)若a=4根号3,b+c=8,求△ABC的面积
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![在三角形ABC中,角A,B,C所对的边分别是a,b,c,已知向量m=(cosB,-cosA),向量n=(2c+b,a)且向量m∥向量n(1)求sinB+sinC的取值范围(2)若a=4根号3,b+c=8,求△ABC的面积](/uploads/image/z/5126756-68-6.jpg?t=%E5%9C%A8%E4%B8%89%E8%A7%92%E5%BD%A2ABC%E4%B8%AD%2C%E8%A7%92A%2CB%2CC%E6%89%80%E5%AF%B9%E7%9A%84%E8%BE%B9%E5%88%86%E5%88%AB%E6%98%AFa%2Cb%2Cc%2C%E5%B7%B2%E7%9F%A5%E5%90%91%E9%87%8Fm%3D%28cosB%2C-cosA%29%2C%E5%90%91%E9%87%8Fn%3D%EF%BC%882c%2Bb%2Ca%EF%BC%89%E4%B8%94%E5%90%91%E9%87%8Fm%E2%88%A5%E5%90%91%E9%87%8Fn%EF%BC%881%EF%BC%89%E6%B1%82sinB%2BsinC%E7%9A%84%E5%8F%96%E5%80%BC%E8%8C%83%E5%9B%B4%EF%BC%882%EF%BC%89%E8%8B%A5a%3D4%E6%A0%B9%E5%8F%B73%2Cb%2Bc%3D8%2C%E6%B1%82%E2%96%B3ABC%E7%9A%84%E9%9D%A2%E7%A7%AF)
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