MCQ
Tick $(\checkmark)$ the correct answer: If $\Big(\text{x}+\frac{1}{\text{x}}\Big)=5,$ then $\Big(\text{x}^2+\frac{1}{\text{x}^2}\Big)=?$
- A$25$
- B$27$
- ✓$23$
- D$25\frac{1}{25}$
✓
Answer
Correct option: C.
$23$
$\Big(\text{x}+\frac{1}{\text{x}}\Big)=5,$
$\Big(\text{x}+\frac{1}{\text{x}}\Big)^2=(5)^2$
$\Rightarrow\text{x}^2+\frac{1}{\text{x}^2}+2=25$
$\Rightarrow\text{x}^2+\frac{1}{\text{x}^2}+25-2=23$
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