Solve using Matlab only

Recall that a geometric sum is a sum of the form a+ar+ar2+ar3+ (a) Write a function file called geomsust which acopts the values of r,a and n (in that order) as input. arguments and uses a for loop to return the sum of the first, n terms of the geometric series. Test your function for r1/8,a8,n11. (b) Write a function file called goomaum 2 which aceepts the values of r,a and n (in that order) as input arguments and ases the built in command aue to find the sum of the first n terms of the geometrie series. Test your function for r1/8,a8,n10. Hint: Start by defining the vector 0=[0:n1] and then evaluate the vector R=r, 0 , It should be easy to figure ont how to find the sum from there