which term of the ap 121 117 113 .... is its negative term? (hint; fin

1.	which term of the ap 121 117 113 .... is its negative term? (hint; find n for an
Answer» Given AP is:121, 117, 113, ................First term a = 121Common difference d = 117-121 = -4Let nth term is the first negative term in APNow nth tern in AP = a + (n-1)× d = 121 + (n - 1) × (-4) = 121 - 4n + 4 = 125 - 4nNow, we have to find the suitable value of n so that the value of (125 - 4n) is negative.⇒ 125 - 4n < 0⇒ 125 < 4n⇒ 4n > 125⇒ n > 125/4⇒ n > 31.25Since the term can not be in decimal form (term is always taken a positive integer)\xa0So, n = 32\xa0Now, by taking value of n = 32, we getnth term = 125 - 4×32 = 125 - 128 = -3This is the first negative term in the series.So, n = 32Hence, the\xa032nd\xa0term is the first negative term in AP. suppose n th term is 0so 121+(n-1)(-4)=0121-4n+4=0n=125/4 =31.25so 32 nd term is negativeas S32=121-31*4=-3\xa0\xa0\xa0

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