Check sibling questions

Ex 9.1, 6 - Write first five terms an = n (n2 + 5)/4 - Ex 9.1

Ex 9.1, 6 - Chapter 9 Class 11 Sequences and Series - Part 2
Ex 9.1, 6 - Chapter 9 Class 11 Sequences and Series - Part 3

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Transcript

Ex 8.1 , 6 Write the first five terms of the sequences whose nth term is an = n(n2 +5 )/4 We need to find the first five terms i.e. a1, a2, a3 , a4 and a5 Given an = n (( 2 + 5)/4) Putting n = 1 in (1) a1 = 1 ((12+ 5))/4 = 1 ((1 + 5))/4 = 6/4 = 3/2 Putting n = 2 in (1) a2 = 2 ((22 + 5))/4 = 2 ((4 + 5))/4 = 2 9/4 = 9/2 Putting n = 3 in (1) a3 = 3 ((32 + 5))/4 = 3 ((9 + 5))/4 = 3 14/4 = 21/2 Putting n = 4 in (1) a4 = 4 ((42 + 5))/4 = 4 ((16 + 5))/4 = 4 21/4 = 21 Putting n = 5 in (1) a5 = 5 ((52 + 5))/4 = 5 ((25 + 5))/4 = 5 30/4 = 75/2 Hence first five terms are 3/2 , 9/2 , 21/2 , 21 and 75/2 .

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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.