# Thread: Very basic gamma function question

1. ## Very basic gamma function question

Hi,

In the gamma function (shown below), what does "t" stand for?

$\Gamma(z)=\int_{0}^{\infty}t^{z-1}e^{-t}$

2. Originally Posted by rainer
Hi,

In the gamma function (shown below), what does "t" stand for?

$\Gamma(z)=\int_{0}^{\infty}t^{z-1}e^{-t}$

Is part of the variable within the integral sign: you must add "dt" .

Tonio

3. Ah, so is this what you call an "implicit function?" Both the x and y variable (in this case z and t) being involved in the right side of the equation?

Pardon my ignorance if this sounds really ignorant.

4. Originally Posted by rainer
Hi,

In the gamma function (shown below), what does "t" stand for?

$\Gamma(z)=\int_{0}^{\infty}t^{z-1}e^{-t} \, {\color{red} dt}$
t is the dummy variable of integration. This would have been clearer if you wrote the integral correctly (see the red).

5. Thanks.

I guess my basic question is how do I enter the function into my grapher so as to get the famous gamma function graph. Still no luck with this.

6. Originally Posted by rainer
Thanks.

I guess my basic question is how do I enter the function into my grapher so as to get the famous gamma function graph. Still no luck with this.
Unless on your grapher you can define the function using an integral you will not be able to draw it on your grapher.