On December 20, 2023, Brent will stop offering office hours.
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Comment on Prime Divisors
Hey Brent,
Why dont we consider 1 also to be one of the prime factors of 8500 along with 2,5 and 17.
1 isn't a prime number.
1 isn't a prime number.
From the Official Guide: "A prime number is a positive integer that has exactly TWO different positive divisors, 1 and itself."
1 has only one positive divisor, so it is not prime.
My Bad. Thanks for reminding!
Would total number of prime
Good question.
Good question.
Yes, without the word "DIFFERENT," there would be 6 primes in the factorization of 8500.
Cheers,
Brent
Hi Brent,
What questions can be answered wrongly if we don't include 1 into consideration?
Thank you in advance,
If you don't include 1 as a
If you don't include 1 as a divisor (aka factor) of a positive integer, then you risk incorrectly solving questions involving the divisors of numbers.
Consider this Data Sufficiency (partial) question:
What is the value of positive integer n?
Statement 1: n has exactly one positive divisor.
If you don't consider 1 as a given divisor of n, then you'll (incorrectly) conclude that statement 1 is insufficient, since n could equal 2 or 3 or 5, etc
Cheers,
Brent
Hi Brent,
This is a very useful insight,
Thank you very much