2 cot - trigonometric cotangent
9 acc nonzero real, defaults to epsilon()
14 Calculate the cotangent of x to a multiple of eps, with error less
15 in absolute value than .75 * eps.
18 > print cot(1, 1e-5), cot(1, 1e-10), cot(1, 1e-15), cot(1, 1e-20)
19 .64209 .6420926159 .642092615934331 .64209261593433070301
25 NUMBER *qcot(NUMBER *x, NUMBER *eps)
28 sin, cos, tan, sec, csc, epsilon