Question

1.
2.
3.
4.
Answer (Detailed Solution Below)

Option 1 : $198$

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Detailed Solution

सही उत्तर $198$ है।

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Question:

If $x + \frac{1}{x} = 6$, then the value of $x^3 + \frac{1}{x^3}$ is: / यदि $x + \frac{1}{x} = 6$ हो, तो $x^3 + \frac{1}{x^3}$ का मान है:

1.
$198$
2.
$204$
3.
$192$
4.
$210$

Correct Answer: $198$

Correct — $x^3 + \frac{1}{x^3} = (x + \frac{1}{x})^3 - 3(x + \frac{1}{x}) = 216 - 18 = 198$. Distractor (b) comes from computing $6^3 - 12 = 204$, wrongly subtracting $2 \times 6$ instead of $3 \times 6$. / सही उत्तर — $x^3 + \frac{1}{x^3} = 6^3 - 3 \times 6 = 198$। विकल्प (b) $3 \times 6$ के बजाय $2 \times 6$ घटाने की त्रुटि से आता है।

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