Sum of array elements with recursion in JavaScript

Let's now not display the array elements to the console, but find their sum:

function getSum(arr) {
	let sum = arr.shift();
	
	if (arr.length !== 0) {
		sum += getSum(arr);
	}
	
	return sum;
}

console.log(getSum([1, 2, 3]));

Given an array:

let arr = [1, 2, 3, 4, 5];

Use recursion to find the sum of the squares of this array elements.