if the 3rd and the 9th term of an ap are 4 and -8 respectively, which term of this a.p is zero?
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Answer:
The 5th term.
Step-by-step explanation:
a3 = a1 + 2d = 4
a9 = a1 + 8d = -8
Subtracting :
6d = -12
d = -2
So it's the 5th term because:
a5 = a3 + 2(-2)
= 4 - 2(2) = 0