" I3) "(2cos2A+1)/(2cos2A-1)=tan(60^(@)+A)tan(60^(@)-A)

Prove that (2cos2A+1)/(2cos2A-1)=tan(60^(@)+A)tan(60^(@)-A)

Prove the following: (frac(2cos2A+1)(2cos2A-1))=tan(60^@+A)tan(60^@-A)

Prove that (2cos2A+1)/(2cos2A-1)=tan(60^0+A)tan(60^0-A)

Prove that (2cos2A+1)/(2cos2A-1)=tan(60^0+A)tan(60^0-A)dot

Prove that (2cos2A+1)/(2cos2A-1)=tan(60^0+A)tan(60^0-A)dot

Prove that (2 cos 2 theta+1)/(2 cos 2theta-1)=tan(60^@+theta) (tan 60^@-theta)

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 .

(1+tan^(2)60^(@))^(2)=

Show that : (i) (1-sin60^(@))/(cos60^(@))=(tan60^(@)-1)/(tan60^(@)+1) (ii) (cos30^(@)+sin60^(@))/(1+sin30^(@)+cos60^(@))=cos30^(@)

Show that (i) cos60^(@)*cos30^(@)-sin60^(@)*sin30^(@)=cos90^(@) (ii) cos60^(@)=1-2sin^(2)30^(@)=2cos^(2)30^(@)-1 (iii) (tan60^(@)-tan30^(@))/(1+tan60^(@)*tan30^(@))=tan30^(@)