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Matrices

Question
CBSEENMA12032929

If straight A equals open square brackets table row 1 2 cell negative 3 end cell row 5 0 2 row 1 cell negative 1 end cell 1 end table close square brackets comma space straight B equals open square brackets table row 3 cell negative 1 end cell 2 row 4 2 5 row 2 0 3 end table close square brackets space and space straight C equals open square brackets table row 4 1 2 row 0 3 3 row 1 cell negative 2 end cell 3 end table close square brackets.  compute (A + B) and (B – C). Also verify that A+ (B – C) = (A + B) – C.

Solution
straight A equals open square brackets table row 1 2 cell negative 3 end cell row 5 0 2 row 1 cell negative 1 end cell 1 end table close square brackets comma space straight B equals open square brackets table row 3 cell asterisk times 1 end cell 2 row 4 2 5 row 2 0 3 end table close square brackets comma space straight C equals open square brackets table row 4 1 2 row 0 3 2 row 1 cell negative 2 end cell 3 end table close square brackets

straight A plus straight B equals open square brackets table row 1 2 cell negative 3 end cell row 5 0 2 row 1 cell negative 1 end cell 1 end table close square brackets plus open square brackets table row 3 cell negative 1 end cell 2 row 4 2 5 row 2 0 3 end table close square brackets
space space space space space
space space space space space space equals open square brackets table row cell 1 plus 3 end cell cell 2 minus 1 end cell cell negative 3 plus 2 end cell row cell 5 plus 4 end cell cell 0 plus 2 end cell cell 2 plus 5 end cell row cell 1 plus 2 end cell cell negative 1 plus 0 end cell cell 1 plus 3 end cell end table close square brackets equals open square brackets table row 4 1 cell negative 1 end cell row 9 2 7 row 3 cell negative 1 end cell 4 end table close square brackets

straight B minus straight C equals open square brackets table row 3 cell negative 1 end cell 2 row 4 2 5 row 2 0 3 end table close square brackets minus open square brackets table row 4 1 2 row 0 3 2 row 1 cell negative 2 end cell 3 end table close square brackets

space space space space space space space space space space open square brackets table row cell 3 minus 4 end cell cell negative 1 minus 1 end cell cell 2 minus 2 end cell row cell 4 minus 0 end cell cell 2 minus 3 end cell cell 5 minus 2 end cell row cell 2 minus 1 end cell cell 0 plus 2 end cell cell 3 minus 3 end cell end table close square brackets equals open square brackets table row cell negative 1 end cell cell negative 2 end cell 0 row 4 cell negative 1 end cell 3 row 1 2 0 end table close square brackets
Now space

space space space space straight A plus left parenthesis straight B minus straight C right parenthesis equals open square brackets table row 1 2 cell negative 3 end cell row 5 0 2 row 1 cell negative 1 end cell 1 end table close square brackets plus open square brackets table row cell negative 1 end cell cell negative 2 end cell 0 row 4 cell negative 1 end cell 3 row 1 2 0 end table close square brackets

space space space space space space space space space space space space space space space space space space equals open square brackets table row cell 1 minus 1 end cell cell 2 minus 2 end cell cell negative 3 plus 0 end cell row cell 5 plus 4 end cell cell 0 minus 1 end cell cell 2 plus 3 end cell row cell 1 plus 1 end cell cell negative 1 plus 2 end cell cell 1 plus 0 end cell end table close square brackets

therefore space space space space space straight A plus left parenthesis straight B minus straight C right parenthesis space equals space open square brackets table row 0 0 cell negative 3 end cell row 9 cell negative 1 end cell 5 row 2 1 1 end table close square brackets space space space space space space space space space space space space space space space space space space space space space space space space space space space space space... left parenthesis 1 right parenthesis

space space space space space space space left parenthesis straight A plus straight B right parenthesis minus straight C equals open square brackets table row 4 1 cell negative 1 end cell row 9 2 7 row 3 cell negative 1 end cell 4 end table close square brackets minus open square brackets table row 4 1 2 row 0 3 2 row 1 cell negative 2 end cell 3 end table close square brackets

space space space space space space space space space space space space space space space space space space space space equals space open square brackets table row cell 4 minus 4 end cell cell 1 minus 1 end cell cell negative 1 minus 2 end cell row cell 9 minus 0 end cell cell 2 minus 3 end cell cell 7 minus 2 end cell row cell 3 minus 1 end cell cell negative 1 plus 2 end cell cell 4 minus 3 end cell end table close square brackets

therefore space space space left parenthesis straight A plus straight B right parenthesis minus straight C equals open square brackets table row 0 0 cell negative 3 end cell row 9 cell negative 1 end cell 5 row 2 1 1 end table close square brackets space space space space space space space space space space space space space space space space space space space space space space space space space space space space space
From (1) and (2), A + (B - C) = (A + B)-C

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