Web20.(本小题满分14分)已知等差数列 an 的公差d 0,它的前n项和为Sn,若 ... 8 Sn . y2. 1的左、右两个顶点分别为A、B.曲21.(本小题满分14分)已知椭圆x 4. 2. 线C是以A、B. P在第一象限且在曲线C上,直线AP与椭圆相交于另一点T. (1)求曲线C的方程; ... WebOct 25, 2015 · In an AP, if a=1,an=20 and Sn= 399, then n=? Advertisement Expert-Verified Answer 603 people found it helpful Brainly User since , an = a+ (n-1)d 20 = 1 + (n-1)d 19 = …
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WebFeb 26, 2016 · WE HAVE- SN=399 , A=1 & AN=20. {Sn=n/2 (a+an)} =>so lets substitute... 399=n/2 (a+an) 399=n/2 (1+20) 399=n/2 (21) =>lets send 2 and 21 to RHS. 399X2/21=n. … WebWe can conclude that 10, 20, 30…, 500 is an AP with common difference, d = 10. First term, a = 10. Let the number of terms in this AP = n. Using nth term formula, an = a + (n – 1)d. 500 = 10 + (n – 1)10. 490 = (n – 1)10. n – 1 = 49. n = 50. Sum of an AP, Sn = (n/2) [ a + an], here an is the last term, which is given] = (50/2) ×[10 ...
WebFeb 27, 2012 · In an AP if a=1, an= 20 and sn =399 then n is a) 13 b) 38 c) 21 - Maths - Arithmetic Progressions - 1833845 Meritnation.com Class-10 » Maths Arithmetic … WebIn an AP if a = 1, an = 20 and Sn = 399, then n is (A) 19 (B) 21 (C) 38 (D) 42. The sum of first five multiples of 3 is ... Also find S 20. In an AP, if Sn = n (4n + 1), find the AP. 54 EXEMPLAR PROBLEMS. In an AP, if Sn = 3n 2 + 5n and ak = 164, find the value of k. If Sn denotes the sum of first n terms of an AP, prove that. S 12 = 3(S 8 –S 4 )
WebSum of n terms of AP is given by: S n = n 2 2 a 1 + n-1 d where a 1 = first term, d = common difference. S 24-4 = 24-4 2 2 × 1 + 24-4-1 13 ∵ d = 13, n = 24, a 1 = 1 S 20 = 20 2 2 + 19 × 13 = 2490. a n-4 = a 1 + n-4-1 d a 24-4 = 1 + 24-4-1 13 ∵ d = 13, n = 24, a 1 = 1 a 20 = 248. Therefore, the ordered pair S n-4, a n-4 is equal to (2490 ... WebFeb 11, 2013 · if an ap a=1 ,an=20,sn= 399 then n is Asked by anish mishra 11 Feb, 2013, 02:45: PM Expert Answer Sn=399 => n/2 (a + an) = 399 => n/2 ( 1 + 20) = 399 =>n/2 (21) = 399 => n = 399 X 2/21 => n= 38 Answered by 11 Feb, 2013, 05:49: PM Application Videos This video explains the concept of Arithmetic Progression, Solving Linear E...
WebIf an A.P. has a = 1, t n = 20 and s n = 399, then value of n is : A. 20 B. 32 C. 38 D. 40 Answer: Option C Solution (By Examveda Team) S n = 1 2 ( a + l) × n ⇒ 399 = ( 1 + 20) × n 2 ⇒ 399 × 2 = 21 × n ⇒ n = 399 × 2 21 ⇒ n = 19 × 2 ⇒ n = 38 Join The Discussion Related Questions on Progressions How many terms are there in 20, 25, 30 . . . . . . 140?
WebMar 28, 2024 · Objectives: This study aims to investigate the risk factors associated with severity and death from COVID-19 through a systematic review and meta-analysis of the published documents in Iran.Methods: A systematic search was performed based on all articles indexed in Scopus, Embase, Web of Science (WOS), PubMed, and Google Scholar … fixer to fabulous helpers eyeWebIf an AP has a=1, t n=20 and S n=399, then the value of n is A 19 B 32 C 38 D 40 Easy Solution Verified by Toppr Correct option is C) Given, a=1 t n=1+(n−1)d=20 ∴(n−1)d=19 S … can mint grow in cold weatherWebSolution: An arithmetic progression (AP) is a sequence where the two consecutive terms have the same common difference. It is obtained by adding the same fixed number to its previous term. The nth term of an AP is. aₙ = a + (n - 1 )d. a = first term. aₙ = nth term. d = common difference. Considering the question, we get the value as, can mint get you highWebIn an AP, if a =1, an, = 20 and Sn = 399, then find n. ← Prev Question Next Question → +1 vote . 6.6k views. asked Feb 1, 2024 in Mathematics by Kundan kumar (51.5k points) In an … can mint give you heartburnWebAnswer : Let the required numbers in A.P.are (a - d), a and (a + d). Sum of these numbers = (a - d) + a + (a + d) = 3a Product of these numbers = (a - d)× a × (a + d)=a (a 2 - d 2) But given, sum = 24 and product = 440 ∴ 3a = 24 a = 8 and a (a 2 - d 2) = 8 (64 - d 2) = 440 [ a = 8] Or, 64 - d 2 = 55 Or, d 2 = 64 - 55 => d 2 = 9 => d = ± 3 can mint be used on pcWebLas protecciones eléctricas tienen un papel relevante en la seguridad y en la adecuada operación de un sistema eléctrico de potencia. Particularmente, en el caso de la generación y el trasporte, por su importancia requieren un eficiente sistema de protecciones que permita garantizar la integridad de sus elementos y la continuidad del servicio eléctrico. can mint grow in waterWebIn an AP if a = 1, an = 20 and Sn = 399, then n is (A) 19 (B) 21 (C) 38 (D) 42 Home Get Answers to all your Questions Home NCERT In an AP if a = 1, an = 20 and Sn = 399, then n is (A) 19 (B) 21 (C) 38 (D) 42 #Arithmetic Progressions #NCERT #Maths #Exemplar Maths for Class 10 #1.3 #5.2 #5.3 #5.4 #5.1 #9.2 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 can mint help upset stomach