# Five raisied to the nth power of 2

• Dec 9th 2011, 04:45 AM
philuk2000
Five raisied to the nth power of 2
Hi,

I hope this is in the right place. There probably is a very simple answer to the question I have but here goes.

I understand raising to the power but I don't understand the two following statements that are in my programming book; more specifically I do not know how I would write them down on paper.

Five raised to the first power of 2 is 25
Five raised to the second power of 2 is 125

It's confusing me because I know 5^2 is 25 and that 5^3 is 125 so how can "Five raised to the second power of 2 be 125" and how would I express it in laymans terms?

My math isn't great so please keep it simplish! (Rofl)

• Dec 9th 2011, 05:12 AM
Plato
Re: Five raisied to the nth power of 2
Quote:

Originally Posted by philuk2000
Five raised to the first power of 2 is 25
Five raised to the second power of 2 is 125
It's confusing me because I know 5^2 is 25 and that 5^3 is 125 so how can "Five raised to the second power of 2 be 125" and how would I express it in laymans terms?

It is very awkward to say "Five raised to the second power of 2 "
Because you probably mean \$\displaystyle 2^2=4\$. So you have \$\displaystyle 5^4=625\$.

Now five to the third power is \$\displaystyle 5^3=125\$

But \$\displaystyle 5^{2^{3}}=5^8=390625\$, read "5 to the third power of 2.

NOTE that \$\displaystyle 5^{2^{3}}\ne (5^2)^3=5^6\$
• Dec 9th 2011, 07:16 AM
philuk2000
Re: Five raisied to the nth power of 2
Quote:

Originally Posted by Plato
It is very awkward to say "Five raised to the second power of 2 "
Because you probably mean \$\displaystyle 2^2=4\$. So you have \$\displaystyle 5^4=625\$.

Now five to the third power is \$\displaystyle 5^3=125\$

But \$\displaystyle 5^{2^{3}}=5^8=390625\$, read "5 to the third power of 2.

NOTE that \$\displaystyle 5^{2^{3}}\ne (5^2)^3=5^6\$

Blimey! (Thinking) \$\displaystyle 5^{2^{3}}\$ So how do I enter that on a calculator, or more so how is that represented without using the ^ symbol (i.e. like 5x5x5x5 etc.)

Also is "Five raised to the second power of 2 is 125" wrong in the book?

I didn't understand this bit with the funny equals sign. NOTE that \$\displaystyle 5^{2^{3}}\ne (5^2)^3=5^6\$ and when I enter \$\displaystyle (5^2)^3\$ on my calculator i get 15625 so i'm doing something wrong.

Thanks for your help by the way!
• Dec 9th 2011, 07:28 AM
Plato
Re: Five raisied to the nth power of 2
Quote:

Originally Posted by philuk2000
\$\displaystyle 5^{2^{3}}\$ So how do I enter that on a calculator, or more so how is that represented without using the ^ symbol (i.e. like 5x5x5x5 etc.

I do not know much about calculators. But in computer algebra we could enter 5^(2^3) using parentheses where needed.

Quote:

Originally Posted by philuk2000
Also is "Five raised to the second power of 2 is 125" wrong in the book?

Again, I do not know the vocabulary of your textbook, or language.
I would read "Five raised to the second power of 2" as \$\displaystyle 5^{(2^2)}=5^4=625\$.
• Dec 9th 2011, 07:46 AM
philuk2000
Re: Five raisied to the nth power of 2
Quote:

Originally Posted by Plato
I do not know much about calculators. But in computer algebra we could enter 5^(2^3) using parentheses where needed.

Interesting, I was entering it as (5^2)^3 now that's making more sense with that answer now.

Quote:

Again, I do not know the vocabulary of your textbook, or language.
It's a C programming book in English.

Quote:

I would read "Five raised to the second power of 2" as \$\displaystyle 5^{(2^2)}=5^4=625\$.
Yes that's exactly how I'm reading it which is why i'm confused why the book states it as 25 and 125 on each line.

The exercise is to write a program that prints 5 raised to the first five powers of 2 and the output of each line is in the format "Five raised to the nth power of 2 is x"

The difficulty is that I cannot use loops or a mod operator and have to print the line individually.

I haven't worked it out yet and the wording hasn't helped

Again, thank you very much for the help.