" (ii) "cos((17 pi)/(2))

Find the value of (i) " sin " ((31pi)/(3)) " (ii) " cos " ((17pi)/(2)) " " (iii) " tan " ((-25pi)/(3)) (iv) " cot " ((13pi)/(4)) " " (v) " sec " ((-25pi)/(3)) " " (vi) " cosec " ((-41pi)/(4))

The sum cos ((pi) / (9)) + cos ((2 pi) / (9)) + cos ((3 pi) / (9)) + ... + cos ((17 pi) / (9 )) =

tan ((11 pi) / (3)) - 2sin ((9 pi) / (3)) - (3) / (4) cos ec ^ (2) ((pi) / (4)) + 4cos ^ ( 2) ((17 pi) / (6)) = (3-2sqrt (3)) / (2)

Prove that (sin(-(11pi)/(3))tan((35pi)/(6))sec(-(7pi)/(3)))/(cos((5pi)/(4))cosc((7pi)/(4))cos((17pi)/(6)))= (2)/(sqrt(3))

The value of cos((pi)/(19))+cos((3 pi)/(19))+cos((5 pi)/(19))++cos((17 pi)/(19)) is (a) (1)/(2)(b)0(c)1 (d)none

The value of the expression sin^(-1)((sin(22 pi))/(7))+cos^(-1)((cos(5 pi))/(3))+tan^(-1)((tan(5 pi))/(7))+sin^(-1)(cos2) is (a) (17 pi)/(42)-2( b) -2( c) (-pi)/(21)-2( d) noneofthese

cos((pi)/(15))cos((2 pi)/(15))cos((pi)/(5))cos((4 pi)/(15))cos((2 pi)/(5))cos((7 pi)/(15)) is equal to

cos ((A) / (2)) + cos ((B) / (2)) - cos ((C) / (2)) = 4cos ((pi + A) / (4)) cos ((pi + B) / (4)) cos ((pi-c) / (4))