सारणिकों के गुणधर्म

न्यूनतम गणना के साथ सारणिकों का मान ज्ञात करने के लिए सारणिकों के गुणों की आवश्यकता होती है। सारणिकों के गुण अवयवों, पंक्ति और स्तंभ संचालन पर आधारित होते हैं, और यह सारणिक का मान अति सुलभ विधि से ज्ञात करने में सहायता करता है।

सारणिकों के गुणधर्म

परस्पर परिवर्तन गुणधर्म

The value of a determinant remains unchanged if the rows and the columns of a determinant are interchanged.

Before the rows and the columns are interchanged

$\bigtriangleup ={\begin{vmatrix}a_{1}&a_{2}&a_{3}\\b_{1}&b_{2}&b_{3}\\c_{1}&c_{2}&c_{3}\end{vmatrix}}$

After the rows and the columns are interchanged

$\bigtriangleup _{1}={\begin{vmatrix}a_{1}&b_{1}&c_{1}\\a_{2}&b_{2}&c_{2}\\a_{3}&b_{3}&c_{3}\end{vmatrix}}$

$\bigtriangleup =\bigtriangleup _{1}$

Verification

$\bigtriangleup =a_{1}{\begin{vmatrix}b_{2}&b_{3}\\c_{2}&c_{3}\end{vmatrix}}-a_{2}{\begin{vmatrix}b_{1}&b_{3}\\c_{1}&c_{3}\end{vmatrix}}+a_{3}{\begin{vmatrix}b_{1}&b_{2}\\c_{1}&c_{2}\end{vmatrix}}$

$\bigtriangleup =a_{1}(b_{2}c_{3}-b_{3}c_{2})-a_{2}(b_{1}c_{3}-b_{3}c_{1})+a_{3}(b_{1}c_{2}-b_{2}c_{1})$

$\bigtriangleup =a_{1}b_{2}c_{3}-a_{1}b_{3}c_{2}-a_{2}b_{1}c_{3}+a_{2}b_{3}c_{1}+a_{3}b_{1}c_{2}-a_{3}b_{2}c_{1}$

$\bigtriangleup _{1}=a_{1}{\begin{vmatrix}b_{2}&c_{2}\\b_{3}&c_{3}\end{vmatrix}}-b_{1}{\begin{vmatrix}a_{2}&c_{2}\\a_{3}&c_{3}\end{vmatrix}}+c_{1}{\begin{vmatrix}a_{2}&b_{2}\\a_{3}&b_{3}\end{vmatrix}}$

$\bigtriangleup _{1}=a_{1}(b_{2}c_{3}-c_{2}b_{3})-b_{1}(a_{2}c_{3}-c_{2}a_{3})+c_{1}(a_{2}b_{3}-b_{2}a_{3})$

$\bigtriangleup _{1}=a_{1}b_{2}c_{3}-a_{1}b_{3}c_{2}-a_{2}b_{1}c_{3}+a_{3}b_{1}c_{2}+a_{2}b_{3}c_{1}-a_{3}b_{2}c_{1}$

Hence $\bigtriangleup =\bigtriangleup _{1}$

If the rows and columns of the matrix are interchanged, then the transpose of the matrix is obtained and the determinant value and the determinant of the transpose are equal.

चिन्ह गुणधर्म

If any two rows or any two columns are interchanged, the sign of the value of the determinant changes.

$\bigtriangleup ={\begin{vmatrix}a_{1}&a_{2}&a_{3}\\b_{1}&b_{2}&b_{3}\\c_{1}&c_{2}&c_{3}\end{vmatrix}}$

After changing any two rows

$\bigtriangleup _{1}={\begin{vmatrix}a_{1}&a_{2}&a_{3}\\c_{1}&c_{2}&c_{3}\\b_{1}&b_{2}&b_{3}\end{vmatrix}}$

$\bigtriangleup =\bigtriangleup _{1}$

Verification

$\bigtriangleup =a_{1}{\begin{vmatrix}b_{2}&b_{3}\\c_{2}&c_{3}\end{vmatrix}}-a_{2}{\begin{vmatrix}b_{1}&b_{3}\\c_{1}&c_{3}\end{vmatrix}}+a_{3}{\begin{vmatrix}b_{1}&b_{2}\\c_{1}&c_{2}\end{vmatrix}}$

$\bigtriangleup =a_{1}(b_{2}c_{3}-b_{3}c_{2})-a_{2}(b_{1}c_{3}-b_{3}c_{1})+a_{3}(b_{1}c_{2}-b_{2}c_{1})$

$\bigtriangleup =a_{1}b_{2}c_{3}-a_{1}b_{3}c_{2}-a_{2}b_{1}c_{3}+a_{2}b_{3}c_{1}+a_{3}b_{1}c_{2}-a_{3}b_{2}c_{1}$

$\bigtriangleup =a_{1}{\begin{vmatrix}b_{2}&b_{3}\\c_{2}&c_{3}\end{vmatrix}}-a_{2}{\begin{vmatrix}b_{1}&b_{3}\\c_{1}&c_{3}\end{vmatrix}}+a_{3}{\begin{vmatrix}b_{1}&b_{2}\\c_{1}&c_{2}\end{vmatrix}}$