js join two arrays

JavaScript
let arr1 = [0, 1, 2];
let arr2 = [3, 5, 7];
let primes = arr1.concat(arr2);

// > [0, 1, 2, 3, 5, 7]const array1 = ["Vijendra","Singh"];
const array2 = ["Singh", "Shakya"];
const array3 = [...array1, ...array2];[1,2,3].concat([4,5,6])
// [1,2,3,4,5,6]// using push and apply to return the same array
const arr1 = ['a', 'b'];
const arr2 = ['c', 'd'];
arr1.push.apply(arr1, arr2);
console.log(arr1) // ['a', 'b', 'c', 'd']
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