Question

Find an of an ap if sn= 2n^2 - 3n

Answer 1

CorrecT QuestioN :-

Find the sum of 5 terms of an AP if Sⁿ = 2n² - 3n .

[ Taking sum of terms as 5 since the number of terms is not given ]

GiveN :-

• Sum of n terms of an AP is given by 2n²-3n.

To FinD:-

• Sum of 5 terms of AP .

SolutioN :-

Here Sum of n term of an AP is given by ,

$\boxed{\red{\sf S_n =2n^2-3n]}}$

=> Sⁿ = 2n² - 3n

=> S⁵ = 2*5² -3*5

=> S⁵ = 2*25 - 15

=> S⁵ = 50 - 15

=> S⁵ = 35

Hence the sum of 5 terms is 35 .

$\Large{\boxed{\pink{\sf S_5 = 35}}}$