If the sum of the first n terms of an AP is what is the first term (that is S1)? Whatis the sum of first two terms? What is the second term? Similarly, find the 3rd, the 10th andthe nth terms.

Question

Philoid · Accepted Answer

We can find the first term as follows:

S₁ = 4 × 1 - 1² = 3

Now; sum of first two terms can be calculated as follows:

S₂ = 4 × 2 - 2²

= 8 - 4 = 4

Hence; second term = 4 – 3 = 1

And d = 1 – 3 = - 2

So, 3rd term can be calculated as follows:

a₃ = a + (n – 1)d

= 3 + 2( - 2) = 3 – 4 = - 1

Similarly, 10th term can be calculated as follows:

a₁₀ = a + 9d

= 3 + 9(- 2)

= 3 – 18

= - 15

If the sum of the first n terms of an AP is what is the first term (that is S1)?Whatis the sum of first two terms? What is the second term? Similarly, find the 3rd, the 10th andthe nth terms.

If the sum of the first n terms of an AP is what is the first term (that is S1)?
Whatis the sum of first two terms? What is the second term? Similarly, find the 3rd, the 10th andthe nth terms.