On the second week of precalculus 11, we learned about geometric sequences and series. In a geometric sequence, each term is multiplied by a constant, known as the common ratio(r).

Geometric Sequences: 7,14,28,56,112..

=  ()

= 7 ()

= 7(512)

= 3584

Geometric Series: 4+12+36+108+324..

Sn= a( – 1) / r- 1

= 4 ( -1) / 3-1

= 4 (19683-1) / 3-1

= 4 (19682) / 2

= 78728 / 2

= 39364

Infinite Geometric Series: 16+ 4+ 1+ 0.25+…

= a/1-r

= 16/ 1- 

= 16/

= 16/ 1- 

= 16/

=