求证:(1)tan(a/2+π/4)+tan(a/2-π/4)=2tana (2)1+cos2a+2sin^2a=2
tan^2a =2tan^2b+1 求证 cos2a +sin^2b=0
已知tan(A-B)/tanA+sin^2C/sin^2A=1,求证:tanA*tanB=tan^2C
已知tan(a-r)/tana+sin^2b/sin^2a=1 ,求证tan^2b=tana*tanr..
求证tana+seca=tan(a/2+π/4)
求证tan(A/2)-{1/(tanA/2)}=-2/tanA
求证tan(a/2)-1/(tana/2)=-2/tana
若a∈(0,π/2)且sin^2 a+cos2a=1/4,求tan a的值
已知A、B是锐角,求证(tan(π+A)+tan(-B))/(1/tan(3π-A)+tan(π/2-B))=tanA*
求证:sin^2A+cos^2A+sinAcosA/sin^2A+cos^2A=tan^2A+1+tanA/tan^2A
求证sin与tan 已知3sinB=sin(2A+B),求证tan(A+B)=2tanA
已知tan(π/4+a)=2,求tana的值,求sin2a+sina平方+cos2a的值
tan(pi/4+a)=0.5 (1)求tana(2)求sin2a-cos^2a/1+cos2a