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by anshumishra » Sat Dec 18, 2010 11:25 am
prachich1987 wrote:The first three terms of a sequence are -2,18 & 38.What is the rule for this sequence?
There could be multiple (unless it is told that they are in AP, or there is some rule stated) , however one which comes to my mind first is :

f(n) = -2 + (n-1)*20

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by towerSpider » Mon Dec 20, 2010 2:27 am
prachich1987 wrote:The first three terms of a sequence are -2,18 & 38.What is the rule for this sequence?

Add twenty each time.
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by N:Dure » Mon Dec 20, 2010 6:01 am
Arithmetic sequence: an = a1 + (n-1) d, where a1 is the first term, n is the term's position and d is the difference

-2 + (n-1) 20 = 20n - 22
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