Without using trigonometric tables, evaluate the following: `(sec37^0)/(cos e c53^0)+2cot15^0cot25^0cot45^0cot75^0cot65^0(sin^2 18^0+sin^2 72^0)`

Without using trigonometric tables, evaIuate the following: sec37^@/(cosec53^@)+2cot15^@cot25^@cot45^@cot75^@cot65^@-3(sin^2 18^@+sin^2 72^@)

Without using trigonometric tables, evaluate each of the following: (sec^2 54^0-cot^2 36^0)/(cos e c^2 57^0-tan^2 33^0)+2sin^2 38^0sec^2 52^0-sin^2 45^0

Without using trigonometric tables, evaluate each of the following: (cos^2 20^0+cos^2 70^0)/(sec^2 50^0-cot^2 40^0)+2cosec^2 58^0-2cot58^0tan32^0- 4tan13^0tan37^0tan45^0tan53^0tan77^0

Without using trigonometric tables, evaluate each of the following: (cos^2 20^0+cos^2 70^0)/(sec^2 50^0-cot^2 40^0)+2cosec^2 58^0-2cot58^0tan32^0- 4tan13^0tan37^0tan45^0tan53^0tan77^0

Without using trigonometric tables, evaluate each of the following: 2/3cosec^2 58^0-2/3cot58^0tan32^0-5/3tan13^0tan37^0tan45^0tan53^0tan77^0

Without using trigonometric tables,evaluate each of the following: (sec^(2)54^(0)-cot^(2)36^(@))/(cos ec^(2)57^(0)-tan^(2)33^(0))+2sin^(2)38^(@)sec^(2)52^(0)-sin^(2)45^(@)

Without using trigonometric tables,evaluate each of the following: (2)/(3)cos ec^(2)58^(@)-(2)/(3)cot58^(@)tan32^(@)-(5)/(3)tan13^(0)tan37^(0)tan45^(@)tan53^(@)tan77^(0)

Without using Trigonometric Tables evaluate the following :- (2cos67^@)/(sin23^@)-(tan40^@)/(cot50^@)-cos0^@+tan15^@tan25^@tan60^@tan65^@tan75^@ .

cot 6^0 cot 42^0 cot 66^0 cot 78^0=1

Without using Trigonometric Tables evaluate the following :- sec^2 10^@-cot^2 80^@+(sin15^@cos75^@+cos15^@sin75^@)/(costhetasin(90^@-theta)+sinthetacos(90^@-theta) .