Which term of the AP 64, 60, 56, 52, 48, …. is 0?

1.	Which term of the AP 64, 60, 56, 52, 48, …. is 0?
Answer» To Find: we need to find n when a_n = 0 Given: The series is 64, 60, 56, 52, 48, … and a_n = 0 a₁ = 64, a₂ = 60 and d = 60 – 64 = –4 (Where a = a₁ is first term, a₂ is second term, a_n is n^th term and d is common difference of given AP) Formula Used: a_n = a + (n - 1)d a_n = 0 = a₁ + (n –1)(– 4) 0 – 64 = (n –1)(– 4) [subtract 64 on both sides] – 64 = (n –1)(– 4) 64 = (n –1)4 [Divide both side by '–'] 16 = (n –1) [Divide both side by 4] n = 17^th [add 1 on both sides] The 17^th term of this AP is equal to 0.

Answer»

To Find: we need to find n when a_n = 0

Given: The series is 64, 60, 56, 52, 48, … and a_n = 0

a₁ = 64, a₂ = 60 and d = 60 – 64 = –4

(Where a = a₁ is first term, a₂ is second term, a_n is n^th term and d is common difference of given AP)

Formula Used: a_n = a + (n - 1)d

a_n = 0 = a₁ + (n –1)(– 4)

0 – 64 = (n –1)(– 4) [subtract 64 on both sides]

– 64 = (n –1)(– 4)

64 = (n –1)4 [Divide both side by '–']

16 = (n –1) [Divide both side by 4]

n = 17^th [add 1 on both sides]

The 17^th term of this AP is equal to 0.

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