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The domain of the function $$f(x) = \frac{\sin^{-1}(x - 3)}{\sqrt{9 - x^2}}$$ is
Let the given function be:
$$ f(x) = \frac{\sin^{-1}(x - 3)}{\sqrt{9 - x^2}} $$
For the function to be defined, the conditions for both the numerator and the denominator must be satisfied simultaneously.
Condition 1: Domain of the inverse sine function in the numerator.
The argument of the inverse sine function must lie within the closed interval from -1 to 1:
$$ -1 \leq x - 3 \leq 1 $$
Add 3 to all parts of the inequality to isolate x:
$$ -1 + 3 \leq x \leq 1 + 3 $$
$$ 2 \leq x \leq 4 $$
This gives the first valid interval for x:
$$ x \in [2, 4] $$
Condition 2: Domain of the square root function in the denominator.
The expression inside the square root in the denominator must be strictly greater than 0 because division by 0 is undefined:
$$ 9 - x^2 > 0 $$
Rearrange the inequality by multiplying by -1, which flips the inequality sign:
$$ x^2 - 9 < 0 $$
Factor the difference of squares:
$$ (x - 3)(x + 3) < 0 $$
This quadratic inequality is satisfied when x lies strictly between the two roots:
$$ -3 < x < 3 $$
This gives the second valid interval for x:
$$ x \in (-3, 3) $$
To find the domain of the complete function, take the intersection of the two individual intervals:
$$ \text{Domain} = [2, 4] \cap (-3, 3) $$
Comparing the boundaries, the lower bound must be at least 2, and the upper bound must be strictly less than 3. Combining these restrictions yields:
$$ 2 \leq x < 3 $$
Written in interval notation, this represents a half-open interval.
Final Answer:
The domain of the function is $$ [2, 3) $$.
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