(1+sin4θ-cos4θ)/(1+sin4θ+cos4θ)-(1+sin4θ+cos4θ)/(1+sin4θ-cos4θ)=(1+2sin2θcos2θ-1+2sin²2θ)/(1+2sin2θcos2θ+2cos²2θ-1)-(1+2sin2θcos2θ+2cos²2θ-1)/(1+2sin2θcos2θ-1+2sin
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