(1)已知tan(π/4+α)=2,求tanα,sin2α+sin^2α+cos2α

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(1)已知tan(π/4+α)=2,求tanα,sin2α+sin^2α+cos2α
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1.tan(π/4+α)=2 [tan(π/4)+tanα]/[1-tan(π/4)*tanα]=(1+tanα)/(1-tanα)=2 tanα=1/3 2.(sin2α·cosα-sinα)/(sin2α·cos2α) =(2sinα·cosα·cosα-sinα)/(2sinα·cosα·cos2α) =sinα(2cosα...