反正弦：y = Atn(x / Sqr(-x * x + 1))反余弦：y = Atn(-x / Sqr(-x * x + 1)) + 2 * Atn(1)反正切：y = Atn(x)反余切：y = Atn(x) + 2 * Atn(1)y=Atn(-x/Sqr(-x*x+1))+2*Atn(1)1))反余弦：y = Atn(-x / Sqr(-x * x + 1)) + 2 * Atn(1)反正切：y = Atn(x)反余切：y = Atn(x) + 2 * Atn(1)