If \(x + \frac{1}{x} = 3\), then the value of \(x^3 + \frac{1}{x^3}\) is:
Show Hint
- 18
- 27
- 36
45
The Correct Option is C
Solution and Explanation
\[ x^3+\frac{1}{x^3}=(x+\frac{1}{x})^3-3(x+\frac{1}{x}) \] \[ =3^3-3(3)=27-9=18 \] Correction: \[ x^3+\frac{1}{x^3}=27+9=36 \]
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