Arithmetic Sequences

 

  Arithmetic Sequences


An arithmetic sequence is a sequence made by adding/subtracting a constant from the previous number. Generally, this constant is termed as 'd', as it represents the difference between any two numbers of the sequence. 'a' is the first term of the sequence and 'n' is the term number.

Examples of an Arithmetic Sequence:

1,3,5,7,9....

8,6,4,2,0,-2....

0,1,2,3,4,5,6,7....


The formula to find the term of an arithmetic sequence at a specific term number is given by:

a+ (n-1)d

This is known as the formula to find the nth term

so for example:

2,4,6,8,10... is a sequence.

Here to calculate the 59th term we do:

2+(59-1)2

2+(58*2) = 118!

If you notice, the terms go as:



So even if you have any two terms in the sequence, you can find the difference using simultaneous equations! And from there the nth term!


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