# Math Help - bell curve

1. ## bell curve

small question, is there an equation that'll give you a graph like a bell curve?

2. Yes, there is:

The one used to calculate the standard normal table is:

$\frac{1}{\sqrt{2\pi}}\int_{-\infty}^{z}{e^{\frac{-x^{2}}{2}}}dx$

For instance, if you have a stats book with the table to compare for fun.

Try integrating the above with z=-1.645. You should get very close to 0.05.

Actually, it's 0.0499849....

3. Originally Posted by Quick
small question, is there an equation that'll give you a graph like a bell curve?
Are you interested to know why there is a factor of $2\pi$ there?

4. Originally Posted by ThePerfectHacker
Are you interested to know why there is a factor of $2\pi$ there?
No, I just wanted to see how to mess with the curve

5. Originally Posted by Quick
small question, is there an equation that'll give you a graph like a bell curve?
Normal density:

$
f(x)=\frac{1}{\sqrt{2 \pi} \sigma} e^{-\frac{(x-\mu)^2}{2 \sigma^2}}
$

RonL