MCQ
$(6^{-1} - 8^{-1})^{-1 }=$
- A$\frac{1}{24}$
- ✓$24$
- C$-24$
- D$-\frac{1}{24}$
✓
Answer
Correct option: B.
$24$
$(6^{-1}-8^{-1})^{-1}=$
$=\Big(\frac{1}{6}-\frac{1}{8}\Big)^{-1}$ $\Big(\text{As},\text{x}^{-1}=\frac{1}{\text{x}}\Big)$
$=\Big(\frac{4-3}{24}\Big)^{-1}$
$=\Big(\frac{1}{24}\Big)^{-1}$
$=\frac{24}{1}$ $\Big(\text{As},\text{x}^{-1}=\frac{1}{\text{x}})$
$=24$
Hence, the correct alternative is option $(b).$
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