MCQ
$a\times (b\times c)+b\times (c\times a)+c\times (a\times b)=$
  • $0$
  • B
    $2[a b c]$
  • C
    $a + b + c$
  • D
    $3[a b c]$

Answer

Correct option: A.
$0$
a
(a) $\because a \times (b \times c) = (b\,.\,c)a - (a\,.\,b)c$

$\therefore a \times (b \times c) + b \times (c \times a) + c \times (a \times b)$

$ = (b\,.\,c)a - (a\,.\,b)c + (b\,.\,a)c - (b\,.\,c)a$$ + (b\,.\,c)a - (a\,.\,c)b$

$=0$, 

{$\because a.b = b.a$ etc.}

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