If a, B and C satisfy a + B + C = 0 and ABC = 8, then the value of 1 / A + 1 / B + 1 / C is () A positive number B negative C zero D nonzero rational number
Choose negative number B
(a+b+c)*(a+b+c)=a^2+b^2+c^2+2ab+2ac+2bc=0
Because ABC = 8
Then a, B and C are not equal to 0
So a ^ 2 + B ^ 2 + C ^ 2 > 0
SO 2 (AB + AC + BC)
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