Exams › SSC CGL (Prelims) › Maths

If \(a + \frac{1}{a} = 12\), then find the value of \(a^2 + \frac{1}{a^2}\).

1. 144
2. 146
3. 142
4. 140

Correct answer: 142

Solution

Using \((a+\frac{1}{a})^2=a^2+\frac{1}{a^2}+2\), we get \(12^2=a^2+\frac{1}{a^2}+2\). Therefore, \(a^2+\frac{1}{a^2}=144-2=142\).

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