Skip to content
GATEiit

GATE CSE 2025 Session 2 Q15: Which predicate-logic formula is valid over the naturals

Question

Let P(x)P(x) be an arbitrary predicate over the domain of natural numbers.

Which ONE of the following statements is TRUE?

Try it: multiple choice: exactly one correct option

Select one option
Wrong answer costs 1/3 mark in GATE.
Show answer and explanation

Answer: A (official GATE 2025 final answer key)

Concept used: The principle of mathematical induction.

First step: Ask which hypotheses force PP on every natural number; for the others, build a predicate true only on some numbers (e.g. P(x)≡x≤1000P(x) \equiv x \le 1000).

Full step-by-step solution

Detailed working, common mistakes and linked mock tests will be available with a free GATEiit account. Log-in is coming soon.

Share this question

WhatsAppDownload image

Source: official GATE 2025 Session 2 CS question paper and final answer key, organised by IIT Roorkee. Question paper · Answer key