નિશ્ચાયકના ગુણધર્મનો ઉપયોગ કરીને સાબિત કરો : $\left|\begin{array}{ccc}0 & a & -b \\ -a & 0 & -c \\ b & c & 0\end{array}\right|=0$
We have,
$\Delta=\left|\begin{array}{ccc}0 & a & -b \\ -a & 0 & -c \\ b & c & 0\end{array}\right|$
Applying $R_{1} \rightarrow c R_{1},$ we have:
$\Delta=\frac{1}{c}\left|\begin{array}{ccc}0 & a c & -b c \\ -a & 0 & -c \\ b & c & 0\end{array}\right|$
Applying $R_{1} \rightarrow R_{1}-b R_{2},$ we have:
$\Delta=\frac{1}{c}\left|\begin{array}{ccc}a b & a c & 0 \\ -a & 0 & -c \\ b & c & 0\end{array}\right|$
$=\frac{a}{c}\left|\begin{array}{ccc}b & c & 0 \\ -a & 0 & -c \\ b & c & 0\end{array}\right|$
Here, the two rows $R_{1}$ and $R_{3}$ are identical.
$\therefore \Delta=0$
ધારો કે $a-2 b+c=1$ છે . જો $f(x)=\left|\begin{array}{lll}{x+a} & {x+2} & {x+1} \\ {x+b} & {x+3} & {x+2} \\ {x+c} & {x+4} & {x+3}\end{array}\right|,$ હોય તો . . .
$\left| {\,\begin{array}{*{20}{c}}{441}&{442}&{443}\\{445}&{446}&{447}\\{449}&{450}&{451}\end{array}\,} \right|$
નિશ્ચાયકના ગુણધર્મનો ઉપયોગ કરી સાબિત કરો કે, $\left|\begin{array}{ccc}1 & 1+p & 1+p+q \\ 2 & 3+2 p & 4+3 p+2 q \\ 3 & 6+3 p & 10+6 p+3 q\end{array}\right|=1$
જો $a + b + c = 0$, તો સમીકરણ $\left| {\,\begin{array}{*{20}{c}}{a - x}&c&b\\c&{b - x}&a\\b&a&{c - x}\end{array}\,} \right| = 0$ નો ઉકેલ મેળવો.
જો ${a^2} + {b^2} + {c^2} = - 2$ અને $f(x) = \left| {\begin{array}{*{20}{c}}{1 + {a^2}x}&{(1 + {b^2})x}&{(1 + {c^2})x}\\{(1 + {a^2})x}&{1 + {b^2}x}&{(1 + {c^2})x}\\{(1 + {a^2})x}&{(1 + {b^2})x}&{1 + {c^2}x}\end{array}} \right|$ તો $f(x)$ એ . . . . બહુપદી ઘાતાંક છે .