Is 43 a prime number?



Don't use plagiarized sources. Get Your Custom Essay on
Is 43 a prime number?
Just from $13/Page
Order Essay

A prime number is one that has as its factors only itself and 1. So for instance 3 is a prime number and 4 is not:

##1xx3=3## and that’s all we can get for 3 so 3 is prime

##1xx4=4, 2xx2=4## – 4 has two sets of factors and so isn’t prime

So are there any factors for 43 other than ##43xx1##?

The quick answer is “no” and so 43 is prime.

The longer answer is that we can try to multiply numbers to get to 43:

43 is odd and so nothing times 2 will work

##4+3=7## which is not divisible by 3, so nothing times 3 will work

43 doesn’t end in 0 or 5 so nothing times 5 will work

##7xx6=42##. Close but no cigar – nothing times 7 will work

##11xx4=44##. Close again but still no – so nothing times 11 will work

##13xx3=39##. Not so close and still doesn’t work – so nothing times 13 will work

##17xx2=34, 17xx3=51##. Not close at all and still doesn’t work – so nothing times 17 will work.

##19xx2=38, 19xx3=57##. Nope – nothing times 19 works

##23xx2=46##. Nope.

And there’s no sense in continuing – if 2 times 23 is too big, nothing beyond this point will be smaller. And, in fact, we could have stopped much earlier because we already knew anything times 2, 3, 4, 5,… wouldn’t work (I think technically the last attempt that was redundant was seeing that 5 was not a factor – but it was good to show definitively that these bigger numbers wouldn’t work).

Show more


Source link

Place your order
(550 words)

Approximate price: $22

Calculate the price of your order

550 words
We'll send you the first draft for approval by September 11, 2018 at 10:52 AM
Total price:
The price is based on these factors:
Academic level
Number of pages
Basic features
  • Free title page and bibliography
  • Unlimited revisions
  • Plagiarism-free guarantee
  • Money-back guarantee
  • 24/7 support
On-demand options
  • Writer’s samples
  • Part-by-part delivery
  • Overnight delivery
  • Copies of used sources
  • Expert Proofreading
Paper format
  • 275 words per page
  • 12 pt Arial/Times New Roman
  • Double line spacing
  • Any citation style (APA, MLA, Chicago/Turabian, Harvard)

Our guarantees

Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.

Money-back guarantee

You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.

Read more

Zero-plagiarism guarantee

Each paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.

Read more

Free-revision policy

Thanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.

Read more

Privacy policy

Your email is safe, as we store it according to international data protection rules. Your bank details are secure, as we use only reliable payment systems.

Read more

Fair-cooperation guarantee

By sending us your money, you buy the service we provide. Check out our terms and conditions if you prefer business talks to be laid out in official language.

Read more

Order your essay today and save 15% with the discount code BANANA