若,且,则角的终边所在象限是_____________
若sin=,则sin=________.
已知sinθ=,cosθ=,则tanθ=________.
化简sin2α+sin2β-sin2αsin2β+cos2αcos2β=______.
已知cos=,0<α<,则sin=________.
已知sinθ-cosθ=,则sin3θ-cos3θ=________.