Search 74,177 tutors
FIND TUTORS
Ask a question
0 0

Find a formula for the arithmetic sequence.

Tutors, please sign in to answer this question.

1 Answer

Find a formula for the arithmetic sequence.
a1=5,d=-4/3

5 = 5+0(–4/3),
5+(-4/3) = 5+1(–4/3),
5+(-4/3)+(-4/3) = 5+2(–4/3),
5+2(–4/3)+(–4/3) = 5+3(–4/3),

5+(n–1)(–4/3)

Comments

Why this is not righ? 
TThis is  I did
 
The common difference is d=-4/3
The initial value is a1=5
 
C=a1-d=5-(-4/3)=19/3
an=dn+c
=-4/3n+19/3
d = -4/3 is right
a1 = 5 is right

So the term numbers (1st line) and sequence will be:
1,     2,              3,              4,          …,      n
5, 5+1(-4/3), 5+2(-4/3), 5+3(-4/3), …, 5+(n-1)(-4/3).

See these articles for more help:
http://www.mathsisfun.com/algebra/sequences-sums-arithmetic.html
http://www.purplemath.com/modules/series3.htm
http://www.wyzant.com/resources/lessons/math/precalculus/series_and_sequences/arithmetic_progression

Woodbridge Arithmetic Sequence tutors