(1+tanα)/(1-tanα)=3+2根号2 则sin2α=

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(1+tanα)/(1-tanα)=3+2根号2 则sin2α=

tan(α+π/4)=3+2根号2
sin2α=-cos(2α+π/2)==-cos2(α+π/4)=-[1-tan^2(α+π/4)]/[1+tan^2(α+π/4)]=(2/3)√2