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Ex 5.2

Ex 5.2, 1

Ex 5.2, 2 (i) (MCQ)

Ex 5.2, 2 (ii) (MCQ) Important

Ex 5.2, 3 (i)

Ex 5.2, 3 (ii)

Ex 5.2, 3 (iii) Important

Ex 5.2, 3 (iv)

Ex 5.2, 3 (v) Important

Ex 5.2, 4

Ex 5.2, 5 (i)

Ex 5.2, 5 (ii) Important

Ex 5.2, 6 Important

Ex 5.2, 7

Ex 5.2, 8

Ex 5.2, 9 You are here

Ex 5.2, 10

Ex 5.2, 11

Ex 5.2, 12 Important

Ex 5.2, 13 Important

Ex 5.2, 14 Important

Ex 5.2, 15

Ex 5.2, 16

Ex 5.2, 17 Important

Ex 5.2, 18

Ex 5.2, 19

Ex 5.2, 20 Important

Chapter 5 Class 10 Arithmetic Progressions

Serial order wise

Last updated at May 29, 2023 by Teachoo

Ex 5.2, 9 If the 3rd and the 9th terms of an A.P. are 4 and − 8 respectively. Which term of this A.P. is zero. We know that an = a + (n – 1) d Given 3rd term is 4 a3 = a + (3 – 1) d 4 = a + 2d 4 – 2d = a a = 4 – 2d Given 9th term is –8 a9 = a + (9 – 1) d –8 = a + 8d –8 – 8d = a a = –8d – 8 From (1) & (2) 4 – 2d = –8d – 8 –2d + 8d = –8 – 4 6d = –12 d = (−12)/6 d = –2 Putting value of d in (2) a = 4 – 2d = 4 – 2 × (–2) = 4 + 4 = 8 We need to check which term is 0 Lets assume it is nth term of AP So, an = 0, Also, a = 8 & d = – 2 We know that an = a + (n – 1)d Putting values 0 = 8 + (n – 1) × – 2 0 = 8 + n × ( – 2) – 1 × (– 2) 0 = 8 – 2n + 2 0 = 10 – 2n 2n = 10 n = 10/2 n = 5 ∴ 5th term of AP is 0