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  1. If a2 + b2 + c2 = 2a - 2b - 2,then the value of 3a - 2b + c is
    1. 0
    2. 3
    3. 5
    4. 2
Correct Option: C

a2 + b2 + c2 = 2a – 2b – 2
⇒  a2 + b2 + c2 – 2a + 2b + 2 = 0
⇒  a2 – 2a + 1 + b2 + 2b + 1 + c2 = 0
⇒  (a – 1)2 + (b + 1)2 + c2 = 0
⇒  a – 1 = 0 ⇒ a = 1;
⇒  b + 1 = 0 ⇒ b = –1;
and c = 0
∴  3a – 2b + c = 3 × 1 – 2 (–1) + 0
= 3 + 2 = 5



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