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જો $2 X+3 Y=\left[\begin{array}{ll}2 & 3 \\ 4 & 0\end{array}\right]$ અને $3 X+2 Y=\left[\begin{array}{cc}2 & -2 \\ -1 & 5\end{array}\right]$ હોય, તો $X$ અને $Y$ શોધો.
$X=$ $\left[\begin{array}{cc}\frac{2}{5} & -\frac{12}{5} \\ -\frac{11}{5} & 3\end{array}\right]$, $Y = $ $\left[ {\begin{array}{*{20}{c}} {\frac{2}{5}}&{\frac{{13}}{5}} \\ {\frac{{14}}{5}}&{ - 2} \end{array}} \right]$
$X=$ $\left[\begin{array}{cc}\frac{2}{5} & -\frac{12}{5} \\ -\frac{11}{5} & 3\end{array}\right]$, $Y = $ $\left[ {\begin{array}{*{20}{c}} {\frac{2}{5}}&{\frac{{13}}{5}} \\ {\frac{{14}}{5}}&{ - 2} \end{array}} \right]$
$X=$ $\left[\begin{array}{cc}\frac{2}{5} & -\frac{12}{5} \\ -\frac{11}{5} & 3\end{array}\right]$, $Y = $ $\left[ {\begin{array}{*{20}{c}} {\frac{2}{5}}&{\frac{{13}}{5}} \\ {\frac{{14}}{5}}&{ - 2} \end{array}} \right]$
$X=$ $\left[\begin{array}{cc}\frac{2}{5} & -\frac{12}{5} \\ -\frac{11}{5} & 3\end{array}\right]$, $Y = $ $\left[ {\begin{array}{*{20}{c}} {\frac{2}{5}}&{\frac{{13}}{5}} \\ {\frac{{14}}{5}}&{ - 2} \end{array}} \right]$
Solution
$X+Y=\left[\begin{array}{ll}7 & 0 \\ 2 & 5\end{array}\right]$ ………… $(1)$
$X-Y=\left[\begin{array}{ll}3 & 0 \\ 0 & 3\end{array}\right]$ ………… $(2)$
$2 X+3 Y=\left[\begin{array}{ll}2 & 3 \\ 4 & 0\end{array}\right]$ ………… $(3)$
$3 X+2 Y=\left[\begin{array}{cc}2 & -2 \\ -1 & 5\end{array}\right]$ ………… $(4)$
Multiplying equation $(3)$ with $(2)$, we get
$2(2 X+3 Y)=2\left[\begin{array}{ll}2 & 3 \\ 4 & 0\end{array}\right]$
$\Rightarrow 4 X+6 Y=\left[\begin{array}{ll}4 & 6 \\ 8 & 0\end{array}\right]$ ………… $(5)$
Multiplying equation $(4)$ with $( 3 )$, we get
$3(3 X+2 Y)=3\left[\begin{array}{cc}2 & -2 \\ -1 & 5\end{array}\right]$
$\Rightarrow 9 X+6 Y=\left[\begin{array}{cc}6 & -6 \\ -3 & 15\end{array}\right]$ ………… $(6)$
From $( 5 )$ and $( 6 )$, we have
$(4 X+6 Y)-(9 X+6 Y)=\left[\begin{array}{ll}4 & 6 \\ 8 & 0\end{array}\right]-\left[\begin{array}{cc}6 & -6 \\ -3 & 15\end{array}\right]$
$ \Rightarrow – 5X = \left[ {\begin{array}{*{20}{c}}
{4 – 6}&{6 – ( – 6)} \\
{8 – ( – 3)}&{0 – 15}
\end{array}} \right]$ $ = \left[ {\begin{array}{*{20}{c}}
{ – 2}&{12} \\
{11}&{ – 15}
\end{array}} \right]$
$\therefore X = – \frac{1}{5}\left[ {\begin{array}{*{20}{c}}
{ – 2}&{12} \\
{11}&{ – 15}
\end{array}} \right]$ $ = \left[ {\begin{array}{*{20}{c}}
{\frac{2}{5}}&{ – \frac{{12}}{5}} \\
{ – \frac{{11}}{5}}&3
\end{array}} \right]$
$2 X+3 Y=\left[\begin{array}{ll}2 & 3 \\ 4 & 0\end{array}\right]$
Now,
$\Rightarrow 2\left[\begin{array}{cc}\frac{2}{5} & -\frac{12}{5} \\ -\frac{11}{5} & 3\end{array}\right]+3 Y=\left[\begin{array}{ll}2 & 3 \\ 4 & 0\end{array}\right]$
$\Rightarrow\left[\begin{array}{cc}\frac{4}{5} & -\frac{24}{5} \\ -\frac{22}{5} & 6\end{array}\right]+3 Y=\left[\begin{array}{ll}2 & 3 \\ 4 & 0\end{array}\right]$
$\Rightarrow 3 Y=\left[\begin{array}{ll}2 & 3 \\ 4 & 0\end{array}\right]-\left[\begin{array}{cc}\frac{4}{5} & -\frac{24}{5} \\ -\frac{22}{5} & 6\end{array}\right]$
$ \Rightarrow 3Y = $ $\left[ {\begin{array}{*{20}{c}}
{2 – \frac{4}{5}}&{3 + \frac{{24}}{5}} \\
{4 + \frac{{22}}{5}}&{0 – 6}
\end{array}} \right]$ $ = \left[ {\begin{array}{*{20}{c}}
{\frac{6}{5}}&{\frac{{39}}{5}} \\
{\frac{{42}}{5}}&{ – 6}
\end{array}} \right]$
$\therefore Y=\frac{1}{3}\left[\begin{array}{cc}\frac{6}{5} & \frac{39}{5} \\ \frac{42}{5} & -6\end{array}\right]=\left[\begin{array}{cc}\frac{2}{5} & \frac{13}{5} \\ \frac{14}{5} & -2\end{array}\right]$
Similar Questions
એક ઉત્પાદક $x,y,z$ એમ ત્રણ પ્રકારના માલનું ઉત્પાદન કરે છે. તે તેમનું બે બજારમાં વેચાણ કરે છે. વાર્ષિક વેચાણ નીચે દર્શાવેલ છે :
બજાર ઉત્પાદન
Market | $x$ | $y$ | $z$ |
$I$ | $10,000$ | $2,000$ | $18,000$ |
$II$ | $6,000$ | $20,000$ | $8,000$ |
જો $x, y, z$ ની નંગ દીઠ વેચાણકિંમત અનુક્રમે $Rs$ $2.50$, $Rs$ $1.50$ અને $Rs$ $1.00$ હોય, તો શ્રેણિક બીજગણિતની મદદથી પ્રત્યેક બજારમાંથી થતી કુલ આવક શોધો.