Question

The sum of first ‘ n ’ terms of an AP are given by the formula Sₙ = 2n² - n. Then the 4ᵗʰ term is​

Answer 1

Answer:

sum of 5 terms - sum of 4 terms will give us the 4th term of AP

$s5 - s4 = 2 {(5) }^{2} - 5 - (2 {(4)}^{2} - 4) \\ = 2 \times 25 - 5 - (2 \times 16 - 4) \\ = 50 - 5 - (32 - 4) \\ = 45 - 28 \\ = 17$

Answer 2

Answer: 28

Substitute 4 in the place of n

Hope this helps u