Answer:
[tex]a_{87} = -1020[/tex]
Step-by-step explanation:
Given:
The given AP is.
12,0,-12,......
[tex]n=87[/tex]
The first term of an AP [tex]a=12[/tex]
Common difference [tex]d=0-12=-12[/tex]
We use the the formula for nth term of an AP.
[tex]a_{n} = a+(n-1)d[/tex]
for 87th term
[tex]a_{87} = 12+(87-1)(-12)[/tex]
[tex]a_{87} = 12+(86)(-12)[/tex]
[tex]a_{87} = 12+(-1032)[/tex]
[tex]a_{87} = 12-1032[/tex]
[tex]a_{87} = -1020[/tex]
Therefore, The 87th term of given series is -1020.
