console.log(Math.atanh(-1));
// expected output: -Infinity

console.log(Math.atanh(0));
// expected output: 0

console.log(Math.atanh(0.5));
// expected output: 0.549306144334055 (approximately)

console.log(Math.atanh(1));
// expected output: Infinity

Math.atanh(-2);  // NaN
Math.atanh(-1);  // -Infinity
Math.atanh(0);   // 0
Math.atanh(0.5); // 0.5493061443340548
Math.atanh(1);   // Infinity
Math.atanh(2);   // NaN