👉 Practice this question interactively (Hindi / English / AI)

Let r be a real number and f(x) = {2x-r if x≥r; r if x<r}. Then, the equation f(x)=f(f(x)) holds for all real values of x where:

CAT · 2022 · Quant Slot 3
Question:
Let r be a real number and f(x) = {2x-r if x≥r; r if x<r}. Then, the equation f(x)=f(f(x)) holds for all real values of x where:

Options

x≤r
x≥r
x>r
x≠r
Answer: x≤r

Explanation:
For x≥r: f(x)=2x-r. f(f(x))=f(2x-r). If 2x-r≥r, then f(2x-r)=2(2x-r)-r=4x-3r. For f(x)=f(f(x)): 2x-r=4x-3r, giving x=r. For x≥r, the condition holds.

👉 Want AI explanation? Open in MCQ App

← Previous Next →

Recommended articles

Practice More PYQs

📱 Follow Us

Telegram Instagram YouTube