Write four programs in java, one to solve each problem below. These programs should use recursion to solve these problems. Test you programs with the given test data for each problem.

Problem 3: euler Write a recursive method that takes a double value x, and computes the function e^x using the infinite series e^x = 1 + (x^1)/1! + (x^2)/2! + (x^3)/3! + . . . euler(2) returns something close to 7.389056098930649. Due to round off error, the last several digits may differ slightly. Matching 6 digits is sufficient.