Find an equation for the nth term of the arithmetic sequence. -15, -6, 3, 12, ...
Find a pattern. What are you doing to each number to produce the next in the sequence?
plus 9
-15 + 9(n - 1)
yeah, that type has constant change through one term to next
so i'm right?
yeah you can test it, put in values of n, does it generate that sequence
thank you!! can u help with another one
Find an equation for the nth term of the arithmetic sequence. a14 = -33, a15 = 9
sure
that type of sequence, like i said has a cponstant change from one term to the next. like the +9 in the last one..
\[a _{14}=-33 \] and \[a _{15} = 9\]
here they gave you consecutive terms, and told you the sequence is arithmetic
the constant change from one term to the next is 42
yes
so \[a _{n}\]= -579 + 42(n - 1) ??
or is it an = -579 + 42(n + 1)
f the initial term is a1 and the common difference is d, then the nth term of the sequence is given by; an = a1 + (n-1)d - - - By taking the above result further, the nth term can be given also as; an = am + (n-m)d, where am is a random term in the sequence such that n > m.
is my answer right then
an = am + (n-m)*d an = -33 + (n - 15) *42
that isnt one of my answer choices
that more general form for any 2 terms, not just 1 and 2
yeah fix it up , an = initial term a0 + (n -1)*d
an = -33 + (n-14)*42 an = -33 + (n-1-13)*42 an = -33 + (n-1)*42 - (13*42) an = -579 + (n-1)*42
the initial term a0 is -579
thx
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