We started goemetric sequence today. A geometric sequence is defined by its first term and a common ratio. For a geometric sequence, any two consecutive numbers have the same ratio, the common ratio.

With the first term as a and the common ratio as r, the nth term is: an = ar^(n-1).

With this, we can proof the following properties for a geometric sequence:

1.  the square of nth term equals the product of (n-k)th term and (n+k)th term;

2. if {an} and {bn} are two geometri sequences, then {anbn} and {an/bn} are geometric sequences as well.

We can use the given nth term formulae to solve a variety of problems about geometric sequences.

Note, when working on sequences, it is important to make it right with the subscripts.

Homework is as follows:

http://www.newtonchineseschool.org/teachers/wangweidong/HomeworkGeometricSequence.pdf