Roe created a characterization of this function from a series of functions with constraints on their derivatives and antiderivates.  Shirali showed that a seventh-century approximation of it by Bhaskara-Aryabhata was better than approximations derived using modern methods.  Its first through third derivatives at zero are one, zero, and negative one, making a series approximation easy to derive.  With a range between negative one and one, for ten points name this trigonometric function whose derivative is cosine.
Roe created a characterization of this function from a series of functions with constraints on their derivatives and antiderivates.  Shirali showed that a seventh-century approximation of it by Bhaskara-Aryabhata was better than approximations derived using modern methods.  Its first through third derivatives at zero are one, zero, and negative one, making a series approximation easy to derive.  With a range between negative one and one, for ten points name this trigonometric function whose derivative is cosine.
Roe created a characterization of this function from a series of functions with constraints on their derivatives and antiderivates.  