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Mathematics 6 Online
zarkam21:

B??

zarkam21:

1 attachment
Vocaloid:

I am not sure if I am doing this right but: if you remove the sigma sign you just get the series 2k + 4 we replace k with n to get 2n + 4 @sweetburger may I have a second opinion on this?

zarkam21:

@sweetburger

Vocaloid:

so to find a_n you are supposed to subtract Sn - S_(n-1)

zarkam21:

okay

Vocaloid:

hmm let me think a bit on this one

zarkam21:

Sure take your time

Vocaloid:

it's gotta be either B or D :s my math isn't working out well though

zarkam21:

I'm gonna go to bed now because I am exhausted tomorrow we can get some other opinions if that's okay with you?

Vocaloid:

sure

Vocaloid:

sleep well

zarkam21:

You as well =)

zarkam21:

@sweetburger

zarkam21:

@Shadow

zarkam21:

@vannieduval @Vocaloid @katherine @ThisGirlPretty

zarkam21:

@563blackghost

zarkam21:

what do you guys think

Vocaloid:

@sillybilly123 @nnesha I am having a huge brain fart on this, I know the formula is an = Sn - S_n-1 but that's not giving me one of the choices

zarkam21:

@SourMunchkin7806

SourMunchkin7806:

i dont know this one im sorry did you try just saiyan

zarkam21:

@JustSaiyan

zarkam21:

@563blackghost

563blackghost:

This is a hard one for me as well, I mean I have been trying to do this for about an hour now and I am just stuck. I would think it to be B based on `n` but my confidence in this answer is way low....

563blackghost:

sorry :(

zarkam21:

Ugh so like nobody knows I guess

Nnesha:

\[\large\rm a_1= 2(1)+4=6\] first term is 6 2nd term is 8 common difference =8-6=2 formula for nth term is \[\rm \large(common ~~difference)n+(first ~~~term -common~difference)\]

Nnesha:

or this \[\rm a_1+(n-1)d\]

zarkam21:

so C?

zarkam21:

@Nnesha

Nnesha:

no \[\large\rm a_1= 2(1)+4=6\] first term is 6 2nd term is 8 common difference =8-6=2 formula for nth term is \[\rm \large(common ~~difference)n+(first ~~~term -common~difference)\] so plugin the numbers \[\rm \large(2)n+(6-2)\]

Nnesha:

^so B is correct.

zarkam21:

Oh thanks =)

Nnesha:

yw

sweetburger:

n'th term would just be the nth partial sum which for any n must obey the same form of 2n+4. SOrry for being 9 days late on this.

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