#### The Normal Distribution

The normal distribution is a continuous
probability distribution with the following characteristics:

- It is symmetric about the mean
- The curve extends from minus
to plus infinity
- The limit of the total area under
the curve is 1
- The curve is always above the
x-axis, that is f(x) is always positive (where x is a random variable and
f(x) represents the density function)
- The mean=mode=median A random
variable that follows a normal distribution is called a normal random variable.

Standard normal distribution This
is a typical normal distribution where the mean=0 and the variance=1.

Why
the normal distribution is important?

##### Reference

Electronic Textbook
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