Prime Number Problem 21

  • FB Share
  • Abhishek Kumar

    Mar 24th, 2019

  • Priyangshu Pramanick Mar 10th, 2019

    false for 5 which is greater than 3

Model Answer:

A prime number (>3) can only be of the forms 6k+1 or 6k+5. 

Let n=6k+1

But then n+2=6k+3, a composite number divisible by 3

Let n=6k+5

But then n+4=6k+9, a composite number divisible by 3

Thus, the given statement is false.


Abhishek Kumar

Abhishek Kumar

Abhishek did B. Tech. in Computer Science & Engineering from IIT Kanpur in 2005. Thereafter he joined Indian Revenue Service (IRS) in 2006. He has deep interests in science. He authored the book “Mathematics for Learning Physics”, published by Arihant Publications. This book is designed to be used as the first book after class X and addresses difficulty faced by fresh pass-outs from class X in understanding Physics of class XI on account of non-familiarity with mathematical tools(calculus etc)