Question

A number minus the product of $4$ and its reciprocal is less than zero. Find the numbers which satisfy this condition.

• A. Any number less than $-2$ or between $0$ and $2$
• B. Any number between $-2$ and $2$
• C. Any number less than $2$
• D. Any number between $0$ and $2$

Answer 1

Answer: (B)

Any number between $-2$ and $2$

Let the number be x

Then $x-(4\times \frac{1}{x})\le 0$

$\Rightarrow x\le \frac{4}{x}$

$\Rightarrow x^2\le 4$

$\Rightarrow |x|\le 2$

$\Rightarrow -2\le x\le 2$