The domain of definition of the function $f(x)=-\frac{1}{\sqrt{|x|-x}}$ is
Answer & explanation
Correct answer: option 3
If $x ≥ 0, | x | – x > 0 ⇒ x – x > 0$, No solution
If $x < 0, | x | – x > 0 ⇒ –x – x > 0, 2x < 0 ⇒ x ∈ (–∞, 0)$
The domain of definition of the function $f(x)=-\frac{1}{\sqrt{|x|-x}}$ is
Correct answer: option 3
If $x ≥ 0, | x | – x > 0 ⇒ x – x > 0$, No solution
If $x < 0, | x | – x > 0 ⇒ –x – x > 0, 2x < 0 ⇒ x ∈ (–∞, 0)$