関連ワード:  is inverse cos the same as sec    is inverse cos the same as secant    is 1 cos the same as sec    is arc cosine the same as secant    is cos 1 the same as secant    is 1 cos 2x the same as sec 2x    is 1 cos 2 the same as sec 2    is sec the inverse of cos    is inverse cosine the same as secant    sec is inverse of sin or cos