getFibo.js

function getFibo(num) {
    let row = [1, 1];
    
    for (let i = 2; i < num; i++) {
    	row.push(row[i-1] + row[i-2]);
    }
    
    return row[row.length-1];
}

getPrev2Fibos.js

function getPrev2Fibos(num) {
    let row = [1, 1];
    
    for (let i = 2;;i++) {
    	let n = row[i-1] + row[i-2];
    	row.push(n);
      if (n >= num) {
      	break;
      }
    }
    
    return [row[row.length-2], row[row.length-3]] ;
}

isPalindrome.js

function isPalindrome(input) {
    if (input.length == 1) return true;
    
    let odd = input.length % 2;    
    let first = input.slice(0, Math.floor(input.length/2));
    let last = input.slice(Math.floor(input.length/2)+odd);
    
    last = last.split("").reverse().join("");

    return (first == last);
}