If a + b + c = 0, then the value of a2 + b2 + c2

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If a + b + c = 0, then the value of a² + b² + c² is
a² − bc

1. 0
2. 1
3. 2
4. 3

Correct Option: C

a + b + c = 0
⇒ b + c = –a
On squaring both sides,
⇒ (b + c)² = a²
⇒ b² + c² + 2bc = a²
⇒ a² + b² + c² + 2bc = 2a²
⇒ a² + b² + c² = 2a² − 2bc = 2(a² − bc)

∴	a² + b² + c²	=	2(a² − bc)	= 2
	a² − bc		a² − bc

If a + b + c = 0, then the value of	a² + b² + c²	is
	a² − bc