已知π/2<β<α<3π/4,cos(α-β)=12/13,sin(α+β)=-3/5,求sin2α的值.
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角α,β满足sin(α+β)+cos(α+β)=2√2 cos(α+π/4)sinβ，则【 】
若函数f(x)=Asinx-√3cosx的一个零点为π/3，则A=________；f(π/12)=________．
若3sinα-sinβ=√10,α+β=π/2，则sinα=__________，cos2β=_________．
试证(cosA+sinA)/(cosA-sinA)=tan2A+sec2A.
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