In this chapter, we shall study two series known as the Exponential series and Logarithmic series. In our discussion, we shall make use of mathematical tools like formula for sum of an infinite G.P., combinatorial coefficients.
If x is any complex number then the series is called the exponential series. It can be proved mathematically that this exponential series has a sum and we denote it by ex.
We see that as x increases, the value of ex also increases indefinitely. Also, as x decreases, the value of ex tends toward zero. The function ex is one-one.
If x is a real number such that |x|<1, then the series is
called the logarithmic series. It can be proved mathematically that this logarithmic series has the sum equal to log(1 + x).