Question

A= [  3  4 ]                   B = [ 2    -4  ] 
     [ -2  1 ]                         [  1    -3  ]
 
 
 Dadas as matrizes, A- B é:   

Answer 1

E aí Jhow,

muito simples, basta por o sinal de (-) entre as duas matrizes e tudo o que for menos dentro da matriz, você troca o sinal, morô?!

$A= \left(\begin{array}{ccc}~~3&4\\-2&1\\\end{array}\right)~~~~~e~~~~~B= \left(\begin{array}{ccc}2&~~4\\1&-3\\\end{array}\right)\\\\\\ A-B= \left(\begin{array}{ccc}~~3&4\\-2&1\\\end{array}\right)- \left(\begin{array}{ccc}2&-4\\1&-3\\\end{array}\right)\\\\\\ A-B= \left(\begin{array}{ccc}3-2&4-(-4)\\-2-1&1-(-3)\\\end{array}\right)\\\\\\ A-B= \left(\begin{array}{ccc}1&4+4\\-3&1+3\\\end{array}\right)\\\\\\ \lerge\boxed{\boxed{A-B= \left(\begin{array}{ccc}~~1&8\\-3&4\\\end{array}\right)}}|\\-$

Flw brother, tenha ótimos estudos ;D