" 11.Show that "cos30^(@)=sqrt((1+cos60^(@))/(2))

Show that : sin 30^(@)=sqrt((1-cos60^(@))/(2))

Show that : sin 30^(@)=sqrt((1-cos60^(@))/(2))

Show that : cos 60^(@)=2cos^(2)30^(@)-1

Show that : cos 60^(@)=2cos^(2)30^(@)-1

cos 15^(@) =............. A) sqrt((1+cos 30^(@))/(2)) B) sqrt((1-cos 30^(@))/(2)) C) pm sqrt((1+cos 30^(@))/(2)) D) pm sqrt((1- cos30^(@))/(2))

Show that : (1-sin60^(@))/(cos60^(@))=2-sqrt3 .

(log)_(sin30^(@)cos60^(@))=1

Prove that: (cos30^(@)+sin60^(0))/(1+cos60^(@)+sin30^(@))=(sqrt(3))/(2)

Show that 2(cos^(4)60^(@)+sin^(4)30^(@))-(tan^(2)60^(@)+cot^(2)45^(@))+3sec^(2)30^(@)=1/4

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^(@)