化简1+cos2x除以(tanx/2) -(1/ tanx/2),A -1/2sin2xB 1/2sin2xC -2sinxD 2sin2x

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化简1+cos2x除以(tanx/2)-(1/tanx/2),A-1/2sin2xB1/2sin2xC-2sinxD2sin2x化简1+cos2x除以(tanx/2)-(1/tanx/2),A-1/2

化简1+cos2x除以(tanx/2) -(1/ tanx/2),A -1/2sin2xB 1/2sin2xC -2sinxD 2sin2x
化简1+cos2x除以(tanx/2) -(1/ tanx/2),
A -1/2sin2x
B 1/2sin2x
C -2sinx
D 2sin2x

化简1+cos2x除以(tanx/2) -(1/ tanx/2),A -1/2sin2xB 1/2sin2xC -2sinxD 2sin2x
1+cos2x=2(cosx)^2
tanx/2-1/(tanx/2)=(sinx/2)/(cosx/2) - (cosx/2)/(sinx/2)
=[(sinx/2)^2-(cosx/2)^2]/[(sinx/2)*(cosx/2)]
=-cosx/(1/2sinx)
=-2cosx/sinx
原式=2(cosx)^2/(-2cosx/sinx)
=-cosx*sinx=-1/2sin(2x)