Question
If (a + b + c) = 18 and (ab + bc + ca) = 100, then find
the value of (a² + b² + c²).Solution
ATQ,
As we know,
(a + b + c)² = a² + b² + c² + 2(ab + bc + ca)
Or, (18)² = a² + b² + c² + 2 × (100)
So, a² + b² + c² = 324 – 200 = 124
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