请问这是如何变的 2cosa (sina+cosa)+1→√2sin(2a+π/4)+2
(2sin^2a+sin2a)/(1+tana) 整理 =[2sina(sina+cosa)]/[(sina+cosa)
1:已知sina+cosa=根2求sina cosa sin(4方)a+cos(4方)的值
已知tana=2,求下列各式的值(1)2cosa-√2sina/2cosa+√2sina (2)3sin平方a-4sin
sina+cosa/sina-cosa=2 求sin^2a-2sinacosa+1
若 cos2a/sin(a-π/4)= -√2/2,求cosa+sina的值.
若cos2a/sin((a-(π/4))=-(√2)/2,则cosa+sina的值为
证明:2(cosa-cosa)/(1+cosa+cosa)=cosa/(1+sina)-sina/(1+cosa).
tana=-1/2,则2*sina-3*sina*cosa-5*(cosa)*(cosa)的值是
已知(sin²A+4)/(cosA+1)=2,求(cosA+3)*(sinA+1)的值
求证:1+sina+cosa/1+sina-cosa+1-cosa+sina/1+cosa+sina=2/sina
Sin^4a+Sina*Cosa+Cos^2a化简
证明(1-cos^2a)/(sina+cosa)-(sina+cosa)/(tan^2a-1)=sina+cosa