Question

Daca am 2X=(cu o matrice ) (-4 0 pe 0 -6)urmata de un egal(=) ( 0 0 pe 0 0) cum aflu 2X? eu am facut 2x=B -A dar nu mi iese

Answer 1

$2X + \left[\begin{array}{ccc}-4&0\\0&-6\\\end{array}\right] = \left[\begin{array}{ccc}0&0\\0&0\\\end{array}\right]$

Fie $X= \left[\begin{array}{ccc}a&b\\c&d\\\end{array}\right]$

[tex]2* \left[\begin{array}{ccc}a&b\\c&d\\\end{array}\right]+ \left[\begin{array}{ccc}-4&0\\0&-6\\\end{array}\right] = \left[\begin{array}{ccc}0&0\\0&0\\\end{array}\right] \left[\begin{array}{ccc}2a&2b\\2c&2d\\\end{array}\right]+ \left[\begin{array}{ccc}-4&0\\0&-6\\\end{array}\right] = \left[\begin{array}{ccc}0&0\\0&0\\\end{array}\right] \left[\begin{array}{ccc}2a-4&2b\\2c&2d-6\\\end{array}\right]+= \left[\begin{array}{ccc}0&0\\0&0\\\end{array}\right] [/tex]

[tex]2a-4=0 2b=0 2c=0 2d-6=0[/tex]

$b=0 , c=0$

[tex]2a-4=0 2a=4 [/tex]

$a= \frac{4}{2}=2$

[tex]2d-6=0 2d=6 [/tex]

$d= \frac{6}{2}=3$

Acuma ne ducem la matricea pe care noi am notat cu X

X=$\left[\begin{array}{ccc}2&0\\0&3\end{array}\right]$