Solve the following inequalities for x:
$\frac{1}{x} < 1$
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → $(−∞,0)∪(1,∞)$
Given $\frac{1}{x}< 1$. First, we note that $x≠ 0$.
Since $x^2 > 0$ for all $x ∈ R, x ≠0,$
$\frac{1}{x}<1 ⇒ \frac{1}{x}.x^2 < x^2$ (multiplying by $x^2$)
$⇒ x < x^2 ⇒ 0 < x^2-x$
$⇒ x(x-1)>0$ ...(1)
Mark the numbers 0 and 1 on the real line.
By the method of intervals, the inequality (1) is satisfied when $x > 1$ or $x < 0$.
∴ The solution set is $(−∞,0)∪(1,∞)$.