[An editor is available at the bottom of the page to write and execute the scripts.]

Use recursion to solve the following exercises.

1. Write a JavaScript program to calculate the factorial of a number. Go to the editor
In mathematics, the factorial of a non-negative integer n, denoted by n!, is the product of all positive integers less than or equal to n. For example, 5! = 5 x 4 x 3 x 2 x 1 = 120 Click me to see the solution

4. Write a JavaScript program to compute the sum of an array of integers. Go to the editor
Example : var array = [1, 2, 3, 4, 5, 6] Expected Output : 21 Click me to see the solution.

5. Write a JavaScript program to compute the exponent of a number. Go to the editor
Note : The exponent of a number says how many times the base number is used as a factor.
8^{2} = 8 x 8 = 64. Here 8 is the base and 2 is the exponent. Click me to see the solution.

6. Write a JavaScript program to get the first n Fibonacci numbers. Go to the editor
Note : The Fibonacci Sequence is the series of numbers: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, . . . Each subsequent number is the sum of the previous two. Click me to see the solution.