Nodejs Utililty Methods Array Square

Array.prototype.square = function(){
  return Array.from(this, x => x * x)

Array.prototype.square = function(){
    return this.map((element) =>  Math.pow(element,2));}
==
Array.prototype.cube = function(){
    return this.map((element) =>  Math.pow(element,3));}

Array.prototype.square = function () {
  return this.map(function(n) { 
    return n * n; 
  });

Array.prototype.square = function () {
  return this.map(function (e) {
    return e * e;
  });
};

Array.prototype.square = function () {
  return this.map((item) => {
    return Math.pow(item, 2);
  });
};

Array.prototype.square = function(){
    return this.map(function(e){
        return (e * e);
    });
};
Array.prototype.cube = function(){
    return this.map(function(e){
        return (e * e * e);
    });
...

Array.prototype.square = function (){
  var result = this.map(function(v){
      return v*v;
  });
  return result;
};
Array.prototype.cube = function (){
  var result = this.map(function(v){
    return v*v*v;
...

Array.prototype.square = function () { return this.map(elem => elem*elem); }
Array.prototype.cube = function() { return this.map(elem => Math.pow(elem, 3)); }
Array.prototype.average = function () { return this.length > 0 ? this.reduce((a,b) => a+b) / this.length : NaN;  }
Array.prototype.sum = function () { return this.reduce((a,b) => a+b); }
Array.prototype.even = function () { return this.filter(elem => elem % 2 === 0); }
Array.prototype.odd = function () { return this.filter(elem => elem % 2 > 0); }

Array.prototype.square  = function () { return this.map(function(n) { return n*n; }); };
Array.prototype.cube    = function () { return this.map(function(n) { return n*n*n; }); };
Array.prototype.average = function () { return this.sum() / this.length; };
Array.prototype.sum     = function () { return this.reduce(function(a, b) { return a + b; }, 0); };
Array.prototype.even    = function () { return this.filter(function(item) { return 0 === item % 2; }); };
Array.prototype.odd     = function () { return this.filter(function(item) { return 0 !== item % 2; }); };

Array.prototype.square = function()
  var ret = new Array();
  this.forEach(function(a) {
    ret.push(a * a);
  });
  return ret;