Questions on Algebra: Sequences of numbers, series and how to sum them answered by real tutors!

Tutors Answer Your Questions about Sequences-and-series (FREE)

Question 1053689: Use mathematical induction to prove that:
1+2+3+...+n=[n(n+1)]/2
Click here to see answer by stanbon(75887)

Question 1053689: Use mathematical induction to prove that:
1+2+3+...+n=[n(n+1)]/2
Click here to see answer by ikleyn(52788)

Question 1053828: what is the formula of sequence 1,2,1,2,1,2...
Click here to see answer by Edwin McCravy(20056)

Question 1053935: the 10th term of an AP is -27 and the 5th term is -12. what is the 18th term. find also the sum of its 28th terms
Click here to see answer by ikleyn(52788)

Question 1053936: Mr. Agada's initial salary increases every year by #1650, calculate his salary in the next 10th years
Click here to see answer by ikleyn(52788)

Question 1053890: 3,48,30,1200,?
Click here to see answer by ikleyn(52788)

Question 1053952: the 10th term of an AP is -27 and the 5th term is -12. what is the 18th term find also the sum of its 28th terms
Click here to see answer by stanbon(75887)

Question 1054149: Find the to infinity of 1+1/2+1/4+...
Click here to see answer by jim_thompson5910(35256)

Question 1054172: The sum of four consecutive terms of an A.P. is 24 and there products is 945. Find these teams
Click here to see answer by ikleyn(52788)

Question 1054074: The 16th term of an A.P. is 40 and the sum of the first 5 terms is 5. Find the sum of the first 50 terms.
Click here to see answer by Fombitz(32388)

Question 1054237: how do I find the sum of the sequence in this problem;
40+41+42+43+...137

Click here to see answer by Fombitz(32388)

Question 1054237: how do I find the sum of the sequence in this problem;
40+41+42+43+...137

Click here to see answer by ikleyn(52788)

Question 1054296: For each given geometric sequence with 1st term a , common ratio r , nth term
Click here to see answer by ikleyn(52788)

Question 1054364: Find the three numbers in an AP such that their sum is 27 and their product is 504
Click here to see answer by ikleyn(52788)

Question 1054410: Find the missing term of the following arithmetic sequence.

3 ,___ ,31
also the last thing i need is the answer to this:
Find the 14th term in an arithmetic sequence: A(subscript)15= -4, d=-8
i dont need a tutorial i just need the answer for homework, i get to do study sessions on fridays and wedensdays (tomorrow)
Click here to see answer by Boreal(15235)

Question 1054498: Find the value of the following summation:

 


Click here to see answer by Edwin McCravy(20056)

Question 1054496: Evaluate:
4
(sigma sign here) 1/2 r(r+1)
r=1
Click here to see answer by Fombitz(32388)

Question 1054638: Find the following sum .
(1)
Click here to see answer by ikleyn(52788)

Question 1054643: Find the following sum .
(2)
Click here to see answer by ikleyn(52788)

Question 1054497: Write out what is meant by:
4
(sigma symbol here) 1/(2k+1)(2k+3)
k=1
Click here to see answer by Fombitz(32388)

Question 1054887: SUM THIS SERIES:
1^3+(1^3+2^3)+(1^3+2^3+3^3)+.......(1^3+2^3+...50^3)
Click here to see answer by Edwin McCravy(20056)

Question 1054917: the third term of a G.P is 45 and the fifth term is 405. Find the G.P. if the common ratio r is positive
Click here to see answer by Boreal(15235)

Question 1054984: The third terms of a G.P is 63 while its fifth terms is 567 what is the sum of the seven terms
Click here to see answer by Edwin McCravy(20056)

Question 1055082: The Mathematics Club at Einstein High School noticed that the school's
student of the week was chosen using an arithmetic sequence. The name
of every student in the school was listed alphabetically and numbered.
The numbers of the first 5 students chosen are listed below.
21, 26, 31, 36, 41
What will be the number of the 111th student chosen?
Click here to see answer by stanbon(75887)

Question 1055161: The sum of three consecutive even integers is -102. List the numbers from smallest to largest:

Click here to see answer by keviana(1)

Question 1055161: The sum of three consecutive even integers is -102. List the numbers from smallest to largest:

Click here to see answer by ikleyn(52788)

Question 1055244: the sum of three numbers in an increasing geometric series is 84.If the first term is doubled, second term is multiplied with 1 1/2 and the third term is multiplied with 5/8, the terms will be an arithmetic progression. Find the original three terms in the G.P.
Click here to see answer by Edwin McCravy(20056)

Question 1055154: The sum of the second and the third terms of a geometric progression is 6,the sum of the third and the fourth term is -12.find;
(a) first term
(b) common ratio
(c) sum of the first 20 terms
Click here to see answer by Fombitz(32388)

Question 1055422: what # is next? 10 4 60 90 70 18 ?
Click here to see answer by Edwin McCravy(20056)

Question 1055549: Find two integers whose sum is -9 and product is 20
Click here to see answer by Alan3354(69443)

Question 1055549: Find two integers whose sum is -9 and product is 20
Click here to see answer by stanbon(75887)

Question 1055640: Hello.
I have a sequence : 4 8 28 108 608 3108
I can't solve it.
How to do it?
Click here to see answer by addingup(3677)

Question 1055729: What's the pattern?
5 9 13 20 29 40 53
Click here to see answer by Edwin McCravy(20056)

Question 1055828: Given that four integers are consecutive terms of an arithmetic sequence with sum 24 and product 945, what is the biggest of these four integers?
Click here to see answer by KMST(5328)

Question 1055795: Hi,i need to know the next number of the sequences.The question is
23,35,57,711,?.
and also i need to know how to solve these sum.
Reveal it as soon as possible.
thank you.
Click here to see answer by Edwin McCravy(20056)

Question 1055910: 10,11,19,28,....,117
Click here to see answer by ikleyn(52788)

Question 1055904: hi,
i need to know the next number
37, 511, 713,?
Click here to see answer by ikleyn(52788)

Question 1055904: hi,
i need to know the next number
37, 511, 713,?
Click here to see answer by MathTherapy(10552)

Question 1055986: Can you, please, help me write this sequence of numbers in summation notation? Thank you! 12+4+4/3+4/9.
Click here to see answer by Boreal(15235)

Question 1055996: Hello. Can you help me to solve this and find nth (1 0 -1 1 0 -1) Thank for your help
Click here to see answer by ikleyn(52788)

Question 1056005: 10,20,74,100,??
Click here to see answer by Edwin McCravy(20056)

Question 1056025: The nth term of sequence is 5n+10. The sum of consecutive terms is 145. Find the values of thrse terms.
Click here to see answer by stanbon(75887)

Question 1055907: hi,
i need to know the between number
6, 13, ?, 33.And also for another one.The questions are,

__?___,7, 26, 63.
please reveal me as soon as possible

Click here to see answer by Edwin McCravy(20056)

Question 1056123: (768/r^5)r^2
Click here to see answer by ikleyn(52788)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440, 1441..1485, 1486..1530, 1531..1575, 1576..1620, 1621..1665, 1666..1710, 1711..1755, 1756..1800, 1801..1845, 1846..1890, 1891..1935, 1936..1980, 1981..2025, 2026..2070, 2071..2115, 2116..2160, 2161..2205, 2206..2250, 2251..2295, 2296..2340, 2341..2385, 2386..2430, 2431..2475, 2476..2520, 2521..2565, 2566..2610, 2611..2655, 2656..2700, 2701..2745, 2746..2790, 2791..2835, 2836..2880, 2881..2925, 2926..2970, 2971..3015, 3016..3060, 3061..3105, 3106..3150, 3151..3195, 3196..3240, 3241..3285, 3286..3330, 3331..3375, 3376..3420, 3421..3465, 3466..3510, 3511..3555, 3556..3600, 3601..3645, 3646..3690, 3691..3735, 3736..3780, 3781..3825, 3826..3870, 3871..3915, 3916..3960, 3961..4005, 4006..4050, 4051..4095, 4096..4140, 4141..4185, 4186..4230, 4231..4275, 4276..4320, 4321..4365, 4366..4410, 4411..4455, 4456..4500, 4501..4545, 4546..4590, 4591..4635, 4636..4680, 4681..4725, 4726..4770, 4771..4815, 4816..4860, 4861..4905, 4906..4950, 4951..4995, 4996..5040, 5041..5085, 5086..5130, 5131..5175, 5176..5220, 5221..5265, 5266..5310, 5311..5355, 5356..5400, 5401..5445, 5446..5490, 5491..5535, 5536..5580, 5581..5625, 5626..5670, 5671..5715, 5716..5760, 5761..5805, 5806..5850, 5851..5895, 5896..5940, 5941..5985, 5986..6030, 6031..6075, 6076..6120, 6121..6165, 6166..6210, 6211..6255, 6256..6300, 6301..6345, 6346..6390, 6391..6435, 6436..6480, 6481..6525, 6526..6570, 6571..6615, 6616..6660, 6661..6705, 6706..6750, 6751..6795, 6796..6840, 6841..6885, 6886..6930, 6931..6975, 6976..7020, 7021..7065, 7066..7110, 7111..7155, 7156..7200, 7201..7245, 7246..7290, 7291..7335, 7336..7380, 7381..7425, 7426..7470, 7471..7515, 7516..7560, 7561..7605, 7606..7650, 7651..7695, 7696..7740, 7741..7785, 7786..7830, 7831..7875, 7876..7920, 7921..7965, 7966..8010, 8011..8055, 8056..8100, 8101..8145, 8146..8190, 8191..8235, 8236..8280, 8281..8325, 8326..8370, 8371..8415, 8416..8460, 8461..8505, 8506..8550, 8551..8595, 8596..8640, 8641..8685, 8686..8730, 8731..8775, 8776..8820, 8821..8865, 8866..8910, 8911..8955, 8956..9000, 9001..9045, 9046..9090, 9091..9135, 9136..9180, 9181..9225, 9226..9270, 9271..9315, 9316..9360, 9361..9405, 9406..9450, 9451..9495, 9496..9540, 9541..9585, 9586..9630, 9631..9675, 9676..9720, 9721..9765, 9766..9810, 9811..9855, 9856..9900, 9901..9945, 9946..9990, 9991..10035, 10036..10080, 10081..10125, 10126..10170, 10171..10215, 10216..10260, 10261..10305, 10306..10350, 10351..10395, 10396..10440, 10441..10485, 10486..10530, 10531..10575, 10576..10620, 10621..10665, 10666..10710, 10711..10755, 10756..10800, 10801..10845, 10846..10890, 10891..10935, 10936..10980, 10981..11025, 11026..11070, 11071..11115, 11116..11160, 11161..11205, 11206..11250, 11251..11295, 11296..11340, 11341..11385, 11386..11430, 11431..11475, 11476..11520, 11521..11565, 11566..11610, 11611..11655, 11656..11700, 11701..11745, 11746..11790