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प्रश्न
Which term of AP 72,68,64,60,… is 0?
उत्तर
In the given AP, first term, a = 72 and common difference, d =
(68-72) = - 4.
Let its nth term be 0.
Then, Tn = 0
⇒ a + (n-1) d = 0
⇒ 72 + (n-1) × (-4) = 0
⇒ 76- 4n = 0
⇒ 4n =76
⇒n=19
Hence, the 19th term of the given AP is 0.
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