1// 20.2.2.33 Math.tanh(x) 2var $export = require('./_export'); 3var expm1 = require('./_math-expm1'); 4var exp = Math.exp; 5 6$export($export.S, 'Math', { 7 tanh: function tanh(x) { 8 var a = expm1(x = +x); 9 var b = expm1(-x); 10 return a == Infinity ? 1 : b == Infinity ? -1 : (a - b) / (exp(x) + exp(-x)); 11 } 12}); 13