" (i) "sin(11 pi)/(12)

Which of the following quantities are rational? (a) sin((11 pi)/(12))sin((5 pi)/(12))( b) cos ec((9 pi)/(10))sec((4 pi)/(5))(c)sin^(4)((pi)/(8))+cos^(4)((pi)/(8))(d)(1+(cos(2 pi))/(9))(1+(cos(4 pi))/(9))(1+(cos(8 pi))/(9))

Which of the following quantities are rational? (a) sin((11pi)/(12))sin((5pi)/(12)) (b) cos e c((9pi)/(10))sec((4pi)/5) (c) sin^4(pi/8)+cos^4(pi/8) (d) (1+cos(2pi)/9)(1+cos(4pi)/9)(1+cos(8pi)/9)

Which of the following quantities are rational? (a) sin((11pi)/(12))sin((5pi)/(12)) (b) cos e c((9pi)/(10))sec((4pi)/5) (c) sin^4(pi/8)+cos^4(pi/8) (d) (1+cos((2pi)/9))(1+cos((4pi)/9))(1+cos((8pi)/9))

Which of the following quantities are rational? (a) sin((11pi)/(12))sin((5pi)/(12)) (b) cos e c((9pi)/(10))sec((4pi)/5) (c) sin^4(pi/8)+cos^4(pi/8) (d) (1+cos((2pi)/9))(1+cos((4pi)/9))(1+cos((8pi)/9))

tan((11 pi)/(12))

tan((11pi)/12)

sin(-11pi)/(3)

If S= 2+log_(2)sin (pi/12)+log_(2)sin((5pi )/12)+log_(2)sin((11 pi)/(12))+log_(2)sin((29pi)/(12)) . then the value of (2^(-S))

Evaluate : (i) " sin " (pi)/(2) " "(ii) " sin " (5pi)/(12)

Prove that (i) "sin " (7pi)/(12) " cos " (pi)/(2) - "cos " *(7pi)/(12) " sin " (pi)/(4) = (sqrt(3))/(2) (ii) " sin " (pi)/(4) " cos " (pi)/(2) + "cos"(pi)/(4) " sin " (pi)/(12) = (sqrt(3))/(2) (iii) " cos " (2pi)/(3) " cos " (pi)/(4) - " sin " (2pi)/(3) " sin " (pi)/(4) =(-(sqrt(3) +1))/(2sqrt(2))