If S1 S2 S3 Are The Sum Of First N Natural Numbers Their Squares And Their Cubes Respectively Then S3 1 8 S1 By S2 Sq Is Equal To
(1) 1 (2) 3 (3) 9 (4) 10 Solution: S1 = sum of first n natural numbers = n(n+1)/2 S2... View Article
(1) 1 (2) 3 (3) 9 (4) 10 Solution: S1 = sum of first n natural numbers = n(n+1)/2 S2... View Article
(1) a = n, b = 1 (2) a = n, b = 5 (3) a = 1, b =... View Article
If a1, a2, a3 (a1>0) are in GP with common ratio r, then the value of r, for which the... View Article
(1) AP (2) GP (3) HP (4) None of these Solution: bx2+√((a+c)2+4b2)x+ a+c ≥ 0 bx2+((a+c)2+4b2)0.5x+ a+c ≥ 0 Discriminant... View Article
Let the sum of first n1, first n2 and first n3 terms of an AP be denoted by S1, S2... View Article
The sum of the products taken two at a time of the numbers 1, 2, 22,….2n-2, 2n-1 is (1) (1/3)22n... View Article
(1) 19/18 (2) 18/19 (3) 7/18 (4) none of these Solution: Given 9/19 + 99/192 + 999/193 + 9999/194 +….∞... View Article
(1) (2n2+1)/(2n+1) (2) n(n+1)/2(2n+1) (3) (2n2+1)/4(2n+1) (4) none of these Solution: Given series 12/1.3 + 22/3.5 + 32/5.7 +…..+n2/(2n-1)(2n+1) Here... View Article
The sum of the n terms of the series 12/1 + (12+22)/(1+2) + (12+22+32)/(1+2+3) + ….is (1) (n+1)(n+2)/3 (2) n(n+2)/3... View Article
(1) 7 (2) 6 (3) 9 (4) none of these Solution: Given (5+9+13+…n terms)/(7+9+11+…(n+1) terms) = 17/16 (5+9+13+…n terms) =>... View Article
Let f(n) = [(n+50)/100] where [n] denotes the integral part of x . Then (1) ∑n = 1100 f(n) =... View Article
(1+3-1)(1+3-2)(1+3-4)(1+3-8) …..(1+3-2n) is equal to (1) \(\begin{array}{l}\frac{3}{2}(1+3^{-2^{n}})\end{array} \) (2) \(\begin{array}{l}\frac{3}{2}(1-3^{-2^{n}})\end{array} \) (3) \(\begin{array}{l}\frac{3}{2}(1-3^{-2^{n+1}})\end{array} \) (4) none of these Solution: S... View Article
Let ai + bi = 1 (i = 1,2,..n) and a = (1/n)(a1 + a2 +….+an) , b = (1/n)(b1... View Article
(1) ≥ 4 (2) 0 (3) ≤ 4 (4) none of these Solution: Given a, b, c are in HP.... View Article
(1) n2 (2) ≥ n2 (3) ≤ n2 (4) none of these Solution: Arithmetic mean, A of x1, x2, …xn... View Article
(1) e (2) e-1 (3) 3e/2 (4) e/2 Solution: an = Σn/n! = n(n+1)/2n! = (n+1)/2(n-1)! = (n-1+2)/2(n-1)! = (½)... View Article
(1) e (2) 4e (3) 3e (4) 5e Solution: Let Sn = 12 + 28 + 50 + 78 +…tn... View Article
(1) log (8/e) (2) log 8e (3) log e/8 (4) none of these Solution: S = 5/1.2.3 + 7/3.4.5 +... View Article
(1) e(e+1) (2) e(1-e) (3) e(e-1) (4) 3e Solution: Let S = 1+ 3/2! + 7/3! + 15/4! +…∞ Tn... View Article
(1) 5e (2) 3e (3) 7e (4) 2e Solution: Given 12.2/1! +22.3/2! + 32.4/3! +….∞ Tn = n2(n+1)/n! = n(n+1)/(n-1)!... View Article