Quick easy Arithmetic Sequence question! (1 Viewer)

LoveHateSchool · Nov 10, 2011

If a,b,c,d,e are in arithmetic sequence, show that a+e=b+d=2c

I don't know how to show it?

SpiralFlex · Nov 10, 2011

Let us consider for demonstration,

$3,5,7,9$ (This is an A.P right?)

How do we know this, via the "term test."

Term 2 - Term 1 must equal Term 3 - Term 2. You should get a common difference, which should be the same. In this case, 2. More generally,

$T_{2}-T_{1}=T_{3}-T_{2}=....=d$

$b-a=c-b=d-c=e-d$

$b-a=e-d=c-b=d-c$

$a+e=b+d=2c$

asianese · Nov 10, 2011

Not enough sleep spiral...t2 - t1 not t2/t1 =D

SpiralFlex · Nov 10, 2011

I must still have nightmares of the G.P I use to visit. He use to stick needles in Spiral's arm. Spiral cried.

asianese · Nov 10, 2011

Aheheheh goo1!

LoveHateSchool · Nov 11, 2011

Thanks Spi!

Quick easy Arithmetic Sequence question! (1 Viewer)

LoveHateSchool

Retired Sept '14

SpiralFlex

Well-Known Member

asianese

Σ

SpiralFlex

Well-Known Member

asianese

Σ

LoveHateSchool

Retired Sept '14

Users Who Are Viewing This Thread (Users: 0, Guests: 1)