# Determinant (order 3) Calculator

## Calculates the determinant of a square matrix of order 3 and the reciprocal of it.

 $\normal detA=det{A}={\left|\begin{array}\vspace{10} a_{\small 11}& a_{\small 12}& a_{\small 13}\\\vspace{10} a_{\small 21}& a_{\small 22}& a_{\small 23}\\a_{\small 31}& a_{\small 32}& a_{\small 33}\\\end{array}\right|}\\$
 (enter a data after click each cell in matrix) matrix A {aij} 6digit10digit14digit18digit22digit26digit30digit34digit38digit42digit46digit50digit det A 1/ det A
 $\normal \\(1)\ detA={\large\sum_{\small j=1}^{\small n}}a_{\small ij}A_{\small ij},\hspace{20}A_{\small ij}:\ cofactor\\\vspace{10}(2)\ {\left|\begin{array}\vspace{10} a_{\small 11}& a_{\small 12}& a_{\small 13}\\\vspace{10} a_{\small 21}& a_{\small 22}& a_{\small 23}\\a_{\small 31}& a_{\small 32}& a_{\small 33}\\\end{array}\right|}\\\hspace{25}=a_{\small 11}{\left|\begin{array}\vspace{10} a_{\small 22}& a_{\small 23}\\ a_{\small 32}& a_{\small 33}\\\end{array}\right|}-a_{\small 12}{\left|\begin{array}\vspace{10} a_{\small 21}& a_{\small 23}\\ a_{\small 31}& a_{\small 33}\\\end{array}\right|}+a_{\small 13}{\left|\begin{array}\vspace{10} a_{\small 21}& a_{\small 22}\\ a_{\small 31}& a_{\small 32}\\\end{array}\right|}\\\vspace{10}(3)\ {\left|\begin{array}\vspace{10} a_{\small 11}& a_{\small 12}\\\vspace{10} a_{\small 21}& a_{\small 22}\\\end{array}\right|}=a_{\small 11}a_{\small 22}-a_{\small 21}a_{\small 12}\\$
Determinant (order 3)
 [1-1] /1 Disp-Num5103050100200
[1]  2018/04/17 17:20   Male / Under 20 years old / Elementary school/ Junior high-school student / Not at All /
Purpose of use
To find determinants
Comment/Request
There should be a option to find determinants of alphabets

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