Q56 / 150 · MHT CET 2026 (20 April Shift 1) · Mathematics
The domain of the function $f(x) = {}^{(10-x)}C_{(x-6)}$ is...
- A$[6, 10]$
- B$\{6, 7, 8, 9, 10\}$
- C$[6, 8]$
- Correct answerD$\{6, 7, 8\}$
Solution
For the function $f(x) = {}^{(10-x)}C_{(x-6)}$ to be defined, the following conditions must be satisfied:
$10 - x \ge 0 \Rightarrow x \le 10$
$x - 6 \ge 0 \Rightarrow x \ge 6$
$10 - x \ge x - 6 \Rightarrow 2x \le 16 \Rightarrow x \le 8$
Also, $10 - x$ and $x - 6$ must be integers, which implies $x$ must be an integer.
Combining the inequalities, we get $6 \le x \le 8$.
Since $x$ is an integer, the possible values of $x$ are $6, 7, 8$.
Thus, the domain of the function is $\{6, 7, 8\}$.
Answer: $\{6, 7, 8\}$
$10 - x \ge 0 \Rightarrow x \le 10$
$x - 6 \ge 0 \Rightarrow x \ge 6$
$10 - x \ge x - 6 \Rightarrow 2x \le 16 \Rightarrow x \le 8$
Also, $10 - x$ and $x - 6$ must be integers, which implies $x$ must be an integer.
Combining the inequalities, we get $6 \le x \le 8$.
Since $x$ is an integer, the possible values of $x$ are $6, 7, 8$.
Thus, the domain of the function is $\{6, 7, 8\}$.
Answer: $\{6, 7, 8\}$
Hence, the correct answer is option: 'D'.