This is the basic and conceptual question from Chapter name- Arithmetic Progression

Chapter number- 9

Exercise 9.1

Here we have nth term “an = 2n2 – 3n + 1” of the AP and we are asked to find the first term of it.

CBSE DHANPAT RAI publications

Class:- 10th

Understanding CBSE Mathematics

Question 1 ( viii)

Given:By putting n = 1, 2, 3, 4, 5 we get first five term of the sequence

a

_{1}= 2 .1^{2 }– 3.1 + 1 = 0a

_{2}= 2. 2^{2 }– 3.2 + 1 = 3a

_{3}= 2.3^{2}– 3.3 + 1 = 10a

_{4}= 2.4^{2 }– 3.4 + 1 = 21a

_{5}= 2.5^{2 }– 3.5 + 1 = 36∴ The first five terms are 0, 3, 10, 21, 36