MCQ
Which of the following is probability density function for normal variable $X$ with $n$ standard deviation $\sigma$ ?
- A$f ( x )=\frac{1}{\sigma \sqrt{2 \pi}} e ^{-\frac{1}{2}\left(\frac{ x -\mu}{\sigma}\right)} ;-\infty< x <\infty$
- B$f ( x )=\frac{1}{\sigma \sqrt{2 \pi}} e ^{-\left(\frac{ x -\mu}{\sigma}\right)^2} ;-\infty< x <\infty$
- ✓$f(x)=\frac{1}{\sigma \sqrt{2 \pi}} e^{-\frac{1}{2}\left(\frac{x-\mu}{\sigma}\right)^2} ;-\infty$
- D$f(x)=\frac{1}{\sigma \sqrt{2 \pi}} e^{-\frac{1}{2}\left(\frac{x-\mu}{\sigma}\right)^2} ; 0$