If \((π§ + 1/π§)^2\) = 98, compute \( (π§^2 + 1/π§^2)\) .
2014
IfΒ \((π§ + 1/π§)^2\) = 98, computeΒ \( (π§^2 + 1/π§^2)\) .
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Correct answer: 96
Key identity: (z^2 + 1/z^2) = (z + 1/z)^2 - 2.
Given (z + 1/z)^2 = 98, substitute into the identity to get (z^2 + 1/z^2) = 98 - 2 = 96.
Note: This calculation assumes z β 0 so the expressions are defined. The result does not depend on the sign of z + 1/z.