The Math expm1() static method returns e raised to the power of a number, subtracted by 1.
console.log(Math.expm1(0));
// 0
console.log(Math.expm1(1));
// 1.718281828459045
console.log(Math.expm1(-1));
// -0.6321205588285577
console.log(Math.expm1(2));
// 6.38905609893065