(1-sin^4a-cos^4)/(sin^2a-sin^4a) 化简

(1-sin^6a-cos^6a)/(sin^2a-sin^4a) 1-sin^6a-cos^6a分之1-sin^4a-cos^4a 化简 化简1-sin^4a-cos^4a/1-sin^6a-cos^6a 若sin^4a/sin^2b+cos^4a/cos^2b=1,证明sin^4b/sin^2a+cos^4b/cos^2a (cos a)^4+(sin a)^2*(sin a)^2+(sin a)^2=? 化简 1-sin^4a-cos^4a/cos^2a-cos^4a 化简(1-sin^6 a-cos^6 a)/(cos^2 a-cos^4 a)== 化简Sin A + Sin 2A / 1+cos A + 急.三角函数：化简（sin^2a*cos^4a+sin^4acos^2a)/(1-sin^4a-cos^4a) 求值:1-sin^6a-cos^6a/1-sin^4a-cos^4a (1-sin^4a-cos^4a)/(1-sin^6a-cos^6a) （1-sin^6a-cos^6a)/(1-sin^4a-cos^4a)=?