As shown in class, the max likelyhood for lamda extimate is 1/x1, where x1 is the known sample.
In order for the estimator to be unbiased, E[lamda estimate] = lamda.
E[lamda estimate] = E[1/(x1)] = 1/E(x1)
Now the E(x1) would equal the expected value of the generic exponential value, which we know to be 1/lamda.
So, now it can be determined whether or not the estimator is unbiased.
