已知A,B是△ABC的两个内角,
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=
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cos
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+sin
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(其中
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,
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是互相垂直的单位向量),若|
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|=
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.
(1)试问tanA•tanB是否为定值,若是定值,请求出,否则说明理由;
(2)求tanC的最大值,并判断此时三角形的形状.
考点分析:
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已知f(x)=ax+
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圆C
1:x
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2:x
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