" 2."quad " (a) "2cos(pi)/(12)cos(5 pi)/(12)=(1)/(2)

Prove that (i) " 2sin " (5pi)/(12) " sin " (pi)/(12)=(1)/(2) (ii) " 2 cos " (5pi)/(12) " cos " .(pi)/(12)=(1)/(2) (iii) " 2 sin ".(5pi)/(12) " cos " (pi)/(2) = ((2+sqrt(3))/(2))

Prove that (i) " 2sin " (5pi)/(12) " sin " (pi)/(12)=(1)/(2) (ii) " 2 cos " (5pi)/(12) " cos " .(pi)/(12)=(1)/(2) (iii) " 2 sin ".(5pi)/(12) " cos " (pi)/(2) = ((2+sqrt(3))/(2))

prove that cos[(pi)/(5)]-cos[(2 pi)/(5)]=(1)/(2)

Prove that :cos((pi)/(12))-sin((pi)/(12))=(1)/(sqrt(2))

For any alpha in R , prove that cos ^(2) (alpha -(pi)/(4))+ cos ^(2) (alpha + (pi)/(12))- cos ^(2) (alpha -(pi)/(12))=(1)/(2)

Find the value of 2cos((5 pi)/(12))cos((pi)/(12)) and 2sin((5 pi)/(12))cos((pi)/(12))

Prove that, (sin""(5pi)/(12)-cos""(5pi)/(12))/(cos""(5pi)/(12)+sin""(5pi)/(12))=(1)/(sqrt(3))

Prove that 2sin((5 pi)/(12))cos((pi)/(12))=(2+sqrt(3))/(2)

Prove that 2sin((5pi)/12)cos(pi/12)=(2+sqrt3)/2

16 * cos ""(pi)/(12) * cos"" (4pi)/(12) * cos"" (5pi)/(12)= A) sqrt1 B) sqrt2 C) sqrt3 D) sqrt4