Re-write the Equation

**S_David** · Jun12-09, 04:36 AM

Hello,

I have the following equation:

$LaTeX Code: f(x)=\\sum_{r=m}^{M_B}\\,\\sum_{i=0}^{M_B-r}\\,\\sum_{j=0}^{r+i}\\,\\sum_{k=0}^{j(N_B-1)}(-1)^{i+j}{M_B\\choose r}{M_B-r\\choose i}{r+i\\choose j}\\left(\\frac{x}{C}\\right)^k\\,e^{jx/C}$

and I want to write it in the form of

will be any number from 1 up to

, and $LaTeX Code: f(x)=1-e^{x/C}$ for

.

Can anyone help me, please? Because I am not sure about the limits when extracting some values of them.

Regards

**MathematicalPhysicist** · Jun12-09, 05:11 AM

**S_David** · Jun12-09, 09:42 AM

Originally Posted by MathematicalPhysicist

$LaTeX Code: f(x)=1+\\sum_{r=m}^{M_B-1}\\,\\sum_{i=1}^{M_B-r}\\,\\sum_{j=1}^{r+i}\\,\\sum_{k=1}^{j(N_B-1)}(-1)^{i+j}{M_B\\choose r}{M_B-r\\choose i}{r+i\\choose j}\\left(\\frac{x}{C}\\right)^k\\,e^{jx/C}$ .

But this doesn't give us $LaTeX Code: f(x)=1-e^{x/C}$ for

. And we have the problem for the last summation where the limits will be 1 to 0, how to handle this problem?

**S_David** · Jun12-09, 06:03 PM

Where are the mathematician? I really need this one. Please help if you can.