Systems of Equations

�ax �by �c

� � �dx �ey � f

: 2� 2 system

�ax � by � cz � d �

� �ex � fy � gz � h � �ix _� jy _� kz _� l

: 3� 3 system

� The above systems can be solved by PlySmlt2 in TI-84 Plus CE

Arithmetic Sequences

� Properties of an arithmetic sequence u n

:

1 . u

1

: First term 2 . d � u2 �u1 � un

� un

_� 1: Common difference 3 . u � u1 � ( n � 1 ) d : General term ( n th term ) n n n

�

1� � �

1� : The sum of the first n n terms

2 2

4 . S �2 u ( n 1 ) d� �u u � n

: Summation sign

Geometric Sequences

� Properties of a geometric sequence u n

:

1 . u

1

: First term 2 . r � u2 �u1 � un

� un

_� 1

: Common ratio

3 . u u r ^�

n 1 n

�

1

� : General term ( n th term )

1

4 . ^{( 1} n

u � r S ⁾ n

� : The sum of the first n terms 1� r www . seprodstore . com

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