How to do the calculations in Excel?

I would like to learn how to do the calculations in Excel. I am taking Adv. Calculus, Statistics, PDE courses in the Fall semester to fulfill requirements for MFE program. Right now I would like to learn to be able to do the homework in the Excel for those classes so I will be ready for the quant stuff.

How to do the calculations that are not built into Excel, e.g. how to solve quadratic equation or the integral? Are there plug-in(s) that contain extra functions or I would have to use the VBA for that?

Where do I start and what books should I get? I am proficient in C++ and C# but not in VB or VBA. I saw the recommended books list but I am still not sure which one I need.

Thank you!
Thank you, Andy.

I read your guide; it is very nice that I can use C# (my guess I can use managed C++ as well) to write functions for Excel, I never liked VB anyway.

However, I do not want to write the algorithms from scratch like you wrote Black-Scholes option pricer, instead I want to use a math library to solve my homework problems. Do you know of a free or cheap library that will allow me to solve basic math problems, Calculus, Stats, and PDE problems?

Basically, I want my PC to substitute TI-89. I planning to learn MatLab and SAS but first I want to do it in Excel, C++ & C#.

It seems all roads lead to MATLAB; that's what I am going to start using.

Besides Spreadsheet Link for Excel they also have MATLAB Builder for Excel and MATLAB Builder for .NET for royalty-free - hassle free - deployment.

Thanks for your help!