# arithmetic sequences.

• Mar 9th 2013, 09:58 AM
M670
arithmetic sequences.
So my question is asking whats the first term in this an=2n-4 I know the common difference is 2 and it is arithmetic but can't figure out the first term

Thanks for any help
Fyi I tired 0, 1,-2 and n all wrong
• Mar 9th 2013, 10:32 AM
majamin
Re: arithmetic sequences.
There are many possibilities, as your question is not stating the set of n's on which a_n is calculated. Sounds like a high school question which typical means n=1 is the first term. What answer do you get for this value?
• Mar 9th 2013, 10:37 AM
M670
Re: arithmetic sequences.
Sadly its a university course and at n=1 I get -2 as an answer but the online homework rejected that as I stated I have tired 0, 1,-2 and n I have one attempt left...
• Mar 9th 2013, 10:54 AM
majamin
Re: arithmetic sequences.
That's correct (-2). Very strange indeed and it sounds like there is an error in the question. You could try an answer of 1 (as in, n=1), because the most logical answers are not working. Good luck!
• Mar 9th 2013, 11:04 AM
M670
Re: arithmetic sequences.
Now -2 worked I hate webworks