Math 241 – EXCEL

9/23/08

**Review Problems:**

Find all solutions of the system of equations

Find one solution to the system of equations

**Linear Algebra using
EXCEL**

The first important thing to know about vectors/matrices in EXCEL is how to input them. Create the following portion of a spreadsheet named LinAlg

and then use insert -> name -> define to make x have the array as its value

Now try to use x in a formula. To
do so, select a two by two block of cells somewhere, type Ô=xÕ into one of the
cells and then hit **enter while holding down the shift and the control keys**. This is the secret to entering arrays and array
operations in EXCEL.

1. Try entering the formula Ô=SUM(B2:C2*B3:C3)Õ
into a cell. What happens?

2. For more complicated matrix multiplications you will have to use MMULT. Use it to calculate x^2.

3. Use MINVERSE to find the inverse of x.

4. Use MDETERM to find the determinant of x.

5. Starting from the matrix

find x^2, x^4, and x^8. What is the limit of x^n as n tends to infinity?