" ( क) fिड्ड कांतू "cos A cos(60-A)cos(60+A)=(1)/(4)cos3.4

Prove that :cos A cos(60-A)cos(60+A)=(1)/(4)cos3A

Prove that : cos Acos(60-A)cos(60+A)=1/4cos3A

(ii) Prove cos x cos(60-x)cos(60+x)=(1)/(4)cos3x

Prove that: cos A cos(60^(@)-A)cos(60^(@)+A)=(1)/(4)cos3A

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: cos Acos(60^0-A)cos(60^0+A)=1/4cos3A

Prove that: cosA. Cos(60^(@)+A)cos(60^(2)-A)=1/4 cos3A

If A=30^(@) , show that : 4cosAcos(60^(@)-A)*cos(60^(@)+A)=cos3A

cos alpha*cos60-alpha*cos60+alpha-(1)/(4)cos3 alpha

(sec60)(cos60) =……………