Hp 50g Graphing Calculator Instrukcja Użytkownika Pobierz pdf (Strona 354)

Compare these three solutions with the ones calculated with the numerical

Solution with the inverse matrix

The solution to the system A⋅x = b, where A is a square matrix is x = A

This results from multiplying the first equation by A

definition, A

⋅A = I, thus we write I⋅x = A

⋅b. Also, I⋅x = x, thus, we have, x

For the example used earlier, namely,

we can find the solution in the calculator as follows:

which is the same result found earlier.

Solution by “division” of matrices

While the operation of division is not defined for matrices, we can use the

calculator’s / key to “divide” vector b by matrix A to solve for x in the matrix

equation A⋅x = b. This is an arbitrary extension of the algebraic division

operation to matrices, i.e., from A⋅x = b, we dare to write x = b/A

(Mathematicians would cringe if they see this!) This, of course is interpreted as

⋅b, which is the same as using the inverse of A as in the previous

Hp 50g Graphing Calculator Instrukcja Użytkownika Strona 354