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  1. If a + b + c = 3, a2 + b2 + c2 = 6 and
    1
    +
    1
    +
    1
    = 1, where a, b, c are all non-zero, then ‘abc’ is equal to
    abc
    1. 2
      3
    2. 3
      2
    3. 1
      2
    4. 1
      3
Correct Option: B

a + b + c = 3; a2 + b2 + c2 = 6
∴  (a + b + c)2 = a2 + b2 + c2 + 2ab + 2bc + 2ca
⇒  32 = 6 + 2 (ab + bc + ca)
⇒  9 – 6 = 2(ab + bc + ca)

⇒ ab + bc + ca =
3
2

∴ 
1
+
1
+
1
= 1
abc

⇒ 
bc + ac + ab
= 1
abc

⇒  abc = ab + bc + ca =
3
2



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