已知,则 = .
sin,cos,tan,从小到大的顺序是________.
若|sin(4π-α)|=sin(π+α),则角α的取值范围是________.
若sin=,则sin=________.
已知sinθ=,cosθ=,则tanθ=________.
化简sin2α+sin2β-sin2αsin2β+cos2αcos2β=______.