Sequences And Series, Popular Questions: Jee 1 year MATHS, Math

Arvind asked a question

Subject: Maths, asked on on 21/9/16

If x=1/5+1.3/ 5.10 +1.3.5/5.10.15 +....infinite, then 3x^2+6x=?
1; 2; 3; 4

Neha asked a question

Subject: Maths, asked on on 8/6/17

If x⁶ - 12x⁵ + ax⁴ + bx³ + cx² + dx + 64 = 0 has positive roots then find a,b,c,d.

Pankaj Mandrawal asked a question

Subject: Maths, asked on on 22/10/16

if aⁿ+bⁿ/a^n-1 +b^n-1is a G.M. between a and b, then the value of n is?

Neha asked a question

Subject: Maths, asked on on 8/6/17

If a,b,c are real and distinct , then show that a²(1+b²) + b²(1+c²) +c²(1+a²) > 6abc

Jayant Jain asked a question

Subject: Maths, asked on on 5/8/17

Let a₁,a₂,a₃,.... be in harmonic progression with a₁ = 5 and a₂₀ = 25. The least positive integer n for which a_n < 0 is

Neha asked a question

Subject: Maths, asked on on 8/6/17

If a,b,c,d are positive real numbers prove that bcd/a²+ cda/b² + dab/c² + abc/d² > a+b+c+d

Jayant Jain asked a question

Subject: Maths, asked on on 5/8/17

If the sum of first n terms of an A.P. is cn² , then the sum of squares of these n terms is

Tanishka Gupta asked a question

Subject: Maths, asked on on 10/5/18

Q4. If

x_{1}, x_{2} . . . . . . . . ., x_{n} a n d \frac{1}{h_{1}}, \frac{1}{h_{2}}, . . . . . . . . ., \frac{1}{h_{n}}

are two A.P.s such that x₃ = h₂ = 8 and x₈ = h₇ = 20, then x₅.h₁₀ equals
(A) 2560 (B) 2650 (C) 3200 (D) 1600

Ayaz Ghonia asked a question

Subject: Maths, asked on on 8/7/17

RD Sharma class11th or RD Sharma JEE(Mains & Advanced)

Jayant Jain asked a question

Subject: Maths, asked on on 5/8/17

Suppose that all the terms of an arithmetic progression are natural numbers. If thr ratio of the sum of the first seven terms to the sum of the first eleven terms is 6:11 and the seventh term lies in between 130 and 140 , then the common difference of thid A.P.

Jayant Jain asked a question

Subject: Maths, asked on on 5/8/17

Let the harmonic mean of two positive real number a and b be 4. If q is a positive real number such that a,5,q,b is an arithmeticprogression , then the value(s) of l q - a l is (are)

Jaison asked a question

Subject: Maths, asked on on 27/6/16

is answer 30350 the last question u gave?

Jaison asked a question

Subject: Maths, asked on on 27/6/16

i mean 3050

Shubhrajyoti Ghosh asked a question

Subject: Maths, asked on on 11/3/17

(i) If y is the H.M. between x and z, prove that, 1/(y-x) + 1/(y-z) = 1/x + 1/z
(ii) If harmonic mean of two numbers is 4, their arithmetic mean 'A' and the geometric mean G satisfy the relation 2A + G² = 27. Find the numbers. [ Answer : 6, 3 ]

In order to save time I have given two questions in one post. Please give answer of both the questions ans please donot give any link.

THANK YOU

Sai Prasad B asked a question

Subject: Maths, asked on on 29/3/17

Let T_r be the r^th term of a sequence for r = 1,2,3,..... such that

and T_r > 0

N. If sum of first n terms of this sequence is

and maximum value of T₅ is

where p & q are coprime numbers then value of (p + q) is-

Hrishikesh asked a question

Subject: Maths, asked on on 9/8/17

Plz solve 24 one.

Mayesh Mohapatra asked a question

Subject: Maths, asked on on 14/5/17

The sum of n terms of an AP is 4n(n-1),then what is the sum of their squares

Medha asked a question

Subject: Maths, asked on on 12/10/16

The first and last term of G.P. are a and l respectively; r being its common ratio; then the number of terms in this G.P. is-
a.(log l - log a)/log r
b.l - (log l - log a)/log r
c.(log a - log l)/log r
d.l + (log l - log a)/log r

Hemant asked a question

Subject: Maths, asked on on 14/5/17

If and be two sequences given by a(n) = (x)^(1/2^n) + (y)^(1/2^n) b(n) = (x)^(1/2^n) - (y)^(1/2^n) for all natural n Then a(1)*a(2)*a(3)*...*a(n) = 1. x - y 2. (x + y)/b(n) 3. (x - y)/b(n) 4. xy/b(n)

Medha asked a question

Subject: Maths, asked on on 25/10/16

2+4+7+11+16+....to n terms =???
a.1/6(n²+3n+8)
b.n/6(n²+3n+8)
c.1/6(n²-3n+8)
d.n/6(n²-3n+8)
what to do in this question how to solve pllz give me hint, method of difference we can use here??

Shubhrajyoti Ghosh asked a question

Subject: Maths, asked on on 2/10/17

A pack contains n cards numbered from 1 to n. Two consecutive numbered cards are removed from the pack and the sum of the numbers on the remaining cards is 1224.
If the smaller of the numbers on the removed cards is k, then k – 20 =

Hitesh asked a question

Subject: Maths, asked on on 5/5/17

SEQUENCE AND SERIES QUESTION.

Please explain the highlighted step in the following solution:

Aishik Saha asked a question

Subject: Maths, asked on on 7/8/17

Q 14 17 18 20 22

Janhavi Tarale asked a question

Subject: Maths, asked on on 26/8/17

2,4,11,39.5,?

Janhavi Tarale asked a question

Subject: Maths, asked on on 31/12/17

What will be summation of n^2 from n=1to n=2n

Shubhrajyoti Ghosh asked a question

Subject: Maths, asked on on 11/3/17

A man travels a certain distance with a uniform speed of 5 km/h and returns the same distance with a uniform speed of 4 km/h. What is the average speed of the man?

[ Answer : 40/9 km/h ]

NO LINKS PLEASE

Aishik Saha asked a question

Subject: Maths, asked on on 7/8/17

Q23-25

Sai Prasad B asked a question

Subject: Maths, asked on on 28/3/17

Pls answer this: Let T_r be the r^th term of a sequence for r = 1,2,3,..... such that

and T_r > 0

N. If sum of first n terms of this sequence is

and maximum value of T₅ is

where p & q are coprime numbers then value of (p + q) is- (1) 3381 (2) 3268 (3) 3496 (4) 3167

Guna Shekar asked a question

Subject: Maths, asked on on 2/10/17

solve

129 . S u m t o n t e r m s o f t h e s e r i e s \frac{1}{1 . 2 . 3 . 4} + \frac{1}{2 . 3 . 4 . 5} + \frac{1}{3 . 4 . 5 . 6} + . . . . ., i s (a) \frac{n^{3}}{3 (n + 1) (n + 2) (n + 3)} (b) \frac{n^{3} + 6 n^{2} - 3 n}{6 (n + 2) (n + 3) (n + 4)} (c) \frac{15 n^{2} + 7 n}{4 n (n + 1) (n + 5)} (d) \frac{n^{3} + 6 n^{2} + 11 n}{18 (n + 1) (n + 2) (n + 3)}

Hemant asked a question

Subject: Maths, asked on on 14/5/17

If a and b be two sequences given by a(n) = (x)^(1/2^n) + (y)^(1/2^n) b(n) = (x)^(1/2^n) - (y)^(1/2^n) for all natural n. Then a(1)*a(2)*a(3)*...*a(n) = 1. x - y 2. (x + y)/b(n) 3. (x - y)/b(n) 4. xy/b(n)

Kashif Jamal asked a question

Subject: Maths, asked on on 18/5/18

Solve this :

4.3 I f f o r s o m e p o s i t i v e i n t e g e r n > 1, w e h a v e 1 + x + x^{2} + . . . . . + x^{n - 1} = 0, t h e n \sum_{k = 0}^{n} (x^{k} + \frac{1}{x^{k}}) (A) - 2 (B) - 1 (C) 1 (D) 2

Shubhrajyoti Ghosh asked a question

Subject: Maths, asked on on 11/3/17

If the p^th , q^th and the r^thterm of a H.P. be x, y, z respectively, prove that yz(q-r) + zx(r-p) + xy(p-q) = 0.

NO LINK PLEASE

Prajnesha Singh asked a question

Subject: Maths, asked on on 14/10/16

The sum of the series 1052 − 1032 + 1042 − 1022 + 1032 − 1012 + 1022 − 1002 + … up to 40 terms is

Aditi Chourasia asked a question

Subject: Maths, asked on on 20/3/17

Solve it.
Q). The least value of

a \in R

for which

4 a x^{2} + \frac{1}{x} \geq 1

for all

x > 0

, is
(a)

\frac{1}{64}

(b)

\frac{1}{32}

(c)

\frac{1}{27}

(d)

\frac{1}{25}

Prakhar Pandey asked a question

Subject: Maths, asked on on 3/11/16

casn u explain wht is gp and its formulae

Aditi Chourasia asked a question

Subject: Maths, asked on on 20/3/17

Solve it.
Q). A pack contains n cards numbered from 1 to n. Two consecutive numbered cards are removed from the pack and the sum of the numbers on the remaining cards is 1224. If the smaller of the numbers on the removed cards is k, then

k - 20 =

?

Kalla Kavya Sree asked a question

Subject: Maths, asked on on 7/2/17

Two sides of a rhombus are along the lines,
x−y+1=0 and 7x−y−5=0. If its
diagonals intersect at (−1, −2), then
which one of the following is a vertex of
this rhombus ?

Aditi Chourasia asked a question

Subject: Maths, asked on on 20/3/17

Solve it with explanation.
Q).

a_{1}, a_{2}, a_{3}, . . . . . . ., a_{n} \to A . P

positive terms, then

\frac{a_{1} + a_{2 n}}{\sqrt{a_{1}} + \sqrt{a_{2}}} + \frac{a_{2} + a_{2 n - 1}}{\sqrt{a_{2}} + \sqrt{a_{3}}} + . . . . . . . . . . . . + \frac{a_{n} + a_{n + 1}}{\sqrt{a_{n}} + {\sqrt{a}}_{n + 1}}

Neha asked a question

Subject: Maths, asked on on 8/6/17

if a,b>0, prove that [(1+a)(1+b³)]>3³a²b²

Janhavi Tarale asked a question

Subject: Maths, asked on on 1/1/18

What will be the summation of a^2 if the range is from a=1 to a=2n