The value of `cos e c10^0+cos e c50^0-cos e c70^0` is ____

The value of cos^2 10^0-cos10^0cos50^0+cos^2 50^0 is equal to 4/3 (b) 1/3 (c) 3/4 (d) 3

Find the value of cos12^0+cos84^0+cos156^0+cos132^0

Find the value of x for which cos e c^(-1)(cosx) is defined.

Find the least value of sec^6x+cos e c^6x+sec^6xcos e c^6xdot

cos e c(360^0)/7+cos e c(540^0)/7= cos e c(180^0)/7 (b) cos e c(90^0)/7 sec(180^0)/7 (d) sec(90^0)/7

Find the sum cos e c^(-1)sqrt(10)+cos e c^(-1)sqrt(50)+cos e c^(-1)sqrt(170)++cos e c^(-1)sqrt((n^2+1)(n^2+2n+2))

Which of the following is the greates? cos e c1 (b) cos e c2 cos e c4 (d) cos e c(-6)

If cosx=tany ,coty=tanz ,cotz=tanx , then the value of sinx is (a) 2cos18^0 (b) cos18^0 (c) sin18^0 (d) 2sin18^0

Show that cos10^o cos30^o cos50^o cos70^o =3/16

In A B C , prove that cos e c A/2+cos e c B/2+cos e c C/2geq6.