Inverse Matrix

[Joe Horn]

(06-28-2015 05:01 AM)Lin Su Wrote:  Hi = )!

When i calculate the inverse matrix, i use inv(Matrix) and for small numbers(img.1), there`s no problem but when i try to calculate using large number(img.2)..it shows wrong result..

what am i doing wrong?

(06-28-2015 06:27 AM)salvomic Wrote:  

(06-28-2015 05:01 AM)Lin Su Wrote:  Hi = )!

When i calculate the inverse matrix, i use inv(Matrix) and for small numbers(img.1), there`s no problem but when i try to calculate using large number(img.2)..it shows wrong result..

what am i doing wrong?

large number is the image (2?) with [[4,5][6,7]]?
its inverse is [[-3.5,2.5][3,-2]], correct.
Or am I missing something?

Salvo

The images are displayed on the forum web page in reverse order. By "img.2" he means the image on the left.

Lin: I typed your 5×5 matrix into my Prime, and it gets the correct inverse both in Home and in CAS. Could there be a typo in your input?