MCQ
If $a + b + c = 0,$ then which relation is correct
  • A
    $a = b = c = 0$
  • B
    $a\,.\,b = b\,.\,c = c\,.\,a$
  • $a \times b = b \times c = c \times a$
  • D
    None of these

Answer

Correct option: C.
$a \times b = b \times c = c \times a$
c
(c) Since $a + b + c = 0$

$ \Rightarrow a \times (a + b + c) = 0 \Rightarrow a \times a + a \times b + a \times c = 0$

$ \Rightarrow a \times b = - a \times c = c \times a$ .....$(i)$

Similarly, $b \times (a + b + c) = 0$$ \Rightarrow a \times b = b \times c$.....$(ii)$

By $(i)$ and $(ii),$ we get $a \times b = b \times c = c \times a.$

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