WebAnswer (1 of 7): To get the 1st term, a, n = 1. So, S(1) = a = (4(1) + 3(1^2)) = (4 + 3) = 7. The sum of the first two terms is two times the 1st term plus the difference between terms (i e., a + (a + d) = 2a + d). Since the 1st term is now known, calculating the 2nd term and minusing two times... WebLet S n denote the sum of the first 'n' terms of an A.P. and S 2n=3S n. Then, the ratio S 3n: S n is equal to A 4:1 B 6:1 C 8:1 D 10:1 Medium Solution Verified by Toppr Correct option is B) S n= 2n(n+1) now it is given that S 2n=3S n ⇒ 22n(2n+1)= 23n(n+1) ⇒2(2n+1)=3(n+1) ⇒4n+2=3n+3 ⇒n=1 Then S nS 3n= [n(n+1)/2][3n(3n+1)/2]= 1×23×4=6:1
If the sum of the first n terms of an A.P. is given by Sn=3n2 ... - Quora
WebAug 9, 2024 · It is an arithmetic progression with first term as 5 and common difference as 6 and 20^(th) term is 119 As sum of n terms of a certain series is given by S_n=2n+3n^2, Sum of 20 terms is 2×20+3×20^2=40+1200=1240. Further, sum of 19 terms is 2×19+3×19^2=38+1083=1121,. Hence 20^(th) term is 1240-1121=119. As sum of 1 … WebThe formula for the nth term of a Fibonacci sequence is a_n = a_ (n-1) + a_ (n-2), where a_1 = 1 and a_2 = 1. What is a fibonacci Sequence? A Fibonacci sequence is a sequence of numbers in which each term is the sum of the previous two terms. It is represented by … laguna technopark address
The sum of the first n terms of an A.P. is 3n2 4n. Find the nth term …
WebSum of Squares of The First n Natural Numbers. The squares of natural numbers are: 1 2, 2 2, 3 2, 4 2,…. Or. 1, 4, 9, 16, …. We can express the sum of n terms as: 1 2 + 2 2 + 3 2 +…+ n 2. This is neither AP nor GP since either the difference between two consecutive numbers is not constant or the ratio of two consecutive numbers is constant. WebThe 21st term of the A.P. whose first two terms are -3 and 4 is. Medium. View solution > In an A. P. first two terms are 1 2, 1 6 then 2 5 t h terms is. Medium. View solution > Write the next two terms of A. Webexample 1: Find the sum . example 2: Find the common ratio if the fourth term in geometric series is and the eighth term is . example 3: The first term of a geometric progression is 1, and the common ratio is 5 determine how many terms must be added together to give a sum of 3906. About this calculator Definition: jeep xj steering stabilizer removal