Definition of normal distribution 日X~N(1a3) X is distributed as normal distribution with mean u and variance O2 d The probability density function (PDF) f() for a normal distribution is given by (x f∫(X)= (-∞<X<+∞) G√2兀 Where: e=2.7182818285, base of natural logarithm T=3. 1415926536 ratio of the circumference of a circle to the diameter9 Definition of Normal distribution  X ～ N(, 2 ), X is distributed as normal distribution with mean  and variance  2.  The probability density function (PDF) f (x) for a normal distribution is given by Where: e = 2.7182818285, base of natural logarithm  = 3.1415926536,ratio of the circumference of a circle to the diameter. X f X e 2 2 ( ) 2 1 ( ) 2     − − = (- < X < +)