Question
If (x + y + z) = 14 and (xy + yz + zx) = 50, then find the
value of (x² + y² + z²).Solution
ATQ,
As we know,
(x + y + z)² = x² + y² + z² + 2(xy + yz + zx)
Or, (14)² = x² + y² + z² + 2 × (50)
So, x² + y² + z² = 196 – 100 = 96
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