化简:(sinx+cosx-1)(sinx-cosx+1)/sin2x

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化简:(sinx+cosx-1)(sinx-cosx+1)/sin2x

化简:(sinx+cosx-1)(sinx-cosx+1)/sin2x
化简:(sinx+cosx-1)(sinx-cosx+1)/sin2x

化简:(sinx+cosx-1)(sinx-cosx+1)/sin2x
(sinx+cosx-1)(sinx-cosx+1)/sin2x
=[(sinx)^2-(cosx-1)^2]/sin2x
=[(sinx)^2-(cosx)^2+2cos-1]/sin2x
={-[1-(sinx)^2]-(cosx)^2+2cos}/sin2x
=[-(cosx)^2-(cosx)^2+2cos]/sin2x
=2[cosx-(cosx)^2]/2sinxcosx
=(1-cosx)/sinx
=2[sin(x/2)]^2/2sin(x/2)cos(x/2)
=sin(x/2)/cos(x/2)
=tan(x/2)

[sinx+(cosx-1)][(sinx-(cosx-1)]/2sinxcosx
=[(sinx)^2-(cosx)^2+2cosx-1]/2sinxcosx
=-cotx+1/sinx