tan(A+B)=?tan2A=?

tan(A+B)=?tan2A=? 若tan(a+b)=2,那么tan2a=? tan(a+b)=2/5 tan(a-b)=1/4tan2a= tan（a+b）=3,tan（a-b）=2,则tan2a=? 已知tan(a+b)=3 ,tan(a-b)=5 ,求tan2a 的值. tan(a+b)=2/5,tan(a-b)=1/4,求tana,tanb,tan2a tan(a+b)=2 tan(a-b)=3 tan2a等于? 已知tan(a+b)=3,tan(a-b)=5,求tan2a,tan2b的值~ tan(a+b)=3 tan(a-b)=5 求tan2a tan2b的值 tan(a+b)=5,tan(a-b)=3求tan2a,tan2b的值? tan(a+b)=3,tan(a-b)=5,求tan2a和tan2b的值 tan(A+B)=3,tan(A-B)=5,求tan2A和tan2B的值速答 tan(A-B)=1/2,tan B=-1/7,求tan2A的值速度 数学归纳法tanA*tan2A+tan2A*tan3A+.+tan(n-1)A*tan(nA)=((tannA)/tanA)-n tan(A+B)=3,tan(A-B)=5,求tan2A,tan2B.(A,B是角) tan(A+B)=3,tan(A-B)=5,求tan2A,tan2B.(A,B是角) tan(a b)=4,cot(a-b)=-3,求tan2a和tan2b tan(a+b)=1/2tan(a-b)=1/3.tan2a=______tan2b=_____详细过程,