In the first day of Math class, we study about **Arithmetic sequences. **

This is simple patterns like these ones:

here is the *term*, each *term *are being counted and it has relevancy keeping the numbers like the picture

Ex: T1=2 (t1 is block 1), T2=5(T2 is block 2), T3=8(block 3)……. So you can see the term is bigger so we know that the sequences of this term are “PLUS”. it mean T1=1, T2=5 so if you want to have T2 you need to plus number before T2 with 3: T2=T1 + 3=5

T3=T2 + 3=8. with the above comments, we have this formula:

that is what we call Arithmetic sequences

Second units are **Arithmetic Series.**

Is the term of an arithmetic sequence is added, the result

for example

3,5,7,9,11 —–> Arithmetic sequences

3+5+7+9+11 —–> Arithmetic series

We have the formula:

Third units are **Geometric Sequences**

It is a sequences in which each term after the first obtained by multiplying the preceding term by a fixed nonzero real number called common ratio. The sequences discussed in the last slide

We have the formula:

fourth units are **Infinite Geometric Series**