The COS function saves you a great deal of time and possibly a great deal of head-scratching since you no longer have to remember which side of the triangle is adjacent to the angle, which is the opposite, and which is the hypotenuse.
Iji ọrụ COS nwere ike ịzọpụta gị oge dị ukwuu na ikekwe ọtụtụ ntụrụndụ na-esite ebe ọ bụ na ị gakwaghị echeta akụkụ nke akụkụ triangle dị n'akụkụ akụkụ, nke dị iche, na nke bụ hypotenuse.