tan(a+π/4)=2cos2a 怎么化简

tan(a+π/4)=2cos2a 怎么化简 已知TAN(A+4/π)=2怎cos2A=? tan(π/4+a)=3,求sin2a-2cos2a cos2a/tan(π/4+a), tan(a+π/4)=2,则cos2a+3sin^2a+tan a= tan(a+π/4)=k,则cos2a= tan(a+π/4)=k,则cos2a=? 已知tan(π-a)=-1/2,则cos2a= (cos2a)/tan(π/4+a)化简 已知tan(a+派／4)＝2,则cos2a= tan(a+π/4)=2,则cos2a+3sin^2a+tan2a= tan(a+π/4)=2,则(sin2a-cos²a)/(1+cos2a)=? 已知tan(a+π/4)=2 求cos2a-sin2a/2sinacosa+cos方a 已知tan(π/4+a)=1/2求cos2a/sin2a+cos²a 已知a为第三象限角,cos2a=-3/5,求tan(π/4+2a) tan(π/4+a)=1/2 求(sin2a-cos平方a)÷(1+cos2a) 已知tan(a+π/4)=2 求cos2a+3sin²a得值 已知tan(a+π/4)=2,求cos2a+3sin²a的值