" 3.tan "A,tan(60^(@)+A),tan(60^(@)-A)=tan3A

Prove that: tan A+tan(60^(@)+A)-tan(60^(@)-A)=3tan3A

Prove that: tan A+tan(60^(@)+A)+tan(120^(@)+A)=3tan3A

Prove that tan A. (tan 60^(@) +A). Tan (60^(@)-A)=tan 3A and hence find the value of tan 6^(@) tan 42^(@) tan 66^(@) tan 78^(@) .

Prove that: (i) cos A cos(60^(@)-A)cos (60^(@)+A)=(1)/(4)cos 3A (ii) "tan" A+"tan"(60^(@)+A)-"tan"(60^(@)-A)=3 tan 3A .

Prove that : tan A+tan (60^@+A)-tan (60^@-A)=3 tan 3A .

Prove that tanA+tan(60^@+A)-tan(60^@-A)=3tan3A

Prove that: tanA + tan(60^(@)+A) + tan(120^(@)+A)=3tan3A

Prove that: tanA + tan(60^(@)+A) + tan(120^(@)+A)=3tan3A

Prove the following: tanA+tan(60^@+A)+tan(120^@+A)=3tan3A