-->

Matrices

Question
CBSEENMA12034254

Give example to show that .
 AB = AC but B ≠ C.

Solution
Let space straight A equals space open square brackets table row 1 0 row 0 0 end table close square brackets space comma space straight B equals space open square brackets table row 0 0 row 2 0 end table close square brackets space comma straight C equals space open square brackets table row 0 0 row 0 3 end table close square brackets
therefore space AB equals space open square brackets table row 1 0 row 0 0 end table close square brackets space open square brackets table row 0 0 row 0 2 end table close square brackets space equals space open square brackets table row cell 0 space plus end cell cell 0 space space space space 0 plus 0 end cell row cell 0 space plus end cell cell 0 space space space 0 plus 0 end cell end table close square brackets equals space open square brackets table row 0 0 row 0 0 end table close square brackets equals 0
space space space space space AC equals open square brackets table row 1 0 row 0 0 end table close square brackets space open square brackets table row 0 0 row 3 0 end table close square brackets space equals open square brackets table row cell 0 space plus end cell cell 0 space space space space 0 plus 0 end cell row cell 0 space plus end cell cell 0 space space space 0 plus 0 end cell end table close square brackets equals space open square brackets table row 0 0 row 0 0 end table close square brackets equals 0

therefore space AB equals AC space comma space but space space straight B space not equal to space straight C.