Question
Consider the arithmetic sequence x+2, 18-x, 14+x,...
a) Find the value of x.
b) Find the general term of the arithmetic sequence.
a) Find the value of x.
b) Find the general term of the arithmetic sequence.
Answers
Damon
in general an = a1 + (n-1)d
d = (18-x)-(x+2) = (14+x)-(18-x)
d = 16 -2x = -4 +2x
so
4 x = 20 and x = 5
then d = -4 + 2x = 6
so
an = a1 + (n-1)6
if the first term is x+2 = 7
then the sequence is
an = 7+(n-1)6
d = (18-x)-(x+2) = (14+x)-(18-x)
d = 16 -2x = -4 +2x
so
4 x = 20 and x = 5
then d = -4 + 2x = 6
so
an = a1 + (n-1)6
if the first term is x+2 = 7
then the sequence is
an = 7+(n-1)6
Anonymous
2,10,18,26
nikoru
a1= 2
d=8
n=4
a5=2+(5-1)8
a5=2+32
a5=34
d=8
n=4
a5=2+(5-1)8
a5=2+32
a5=34