Indian Navy Entrance Test Model Paper 5

अवधारणा:
cosec (-x) = -cosec x
cosec ( 2nπ+θ ) = cosec θ
गणना:
हमें (-750°) का मूल्य खोजना होगा
cosec (-750°)
= -cosec (750°) (∵ cosec (-x) = -cosec x)
= -cosec (720° + 30°)
= -cosec( 4π + 30°)
= -cosec 30° (∵ cosec ( 2nπ+θ ) = cosec θ)
= -2