मराठी

Any term of an A.P. (except first) is equal to half the sum of terms which are equidistant from it. - Mathematics

Advertisements
Advertisements

प्रश्न

Any term of an A.P. (except first) is equal to half the sum of terms which are equidistant from it.

पर्याय

  • True

  • False

MCQ
चूक किंवा बरोबर
Advertisements

उत्तर

This statement is True.

Explanation:

Let us consider an A.P a, a + d, a + 2d, …

∴ a2 + a4 = a + d + a + 3d

= 2a + 4d

= 2a3

⇒ a3 = `(a_2 + a_4)/2`

 `(a_3 + a_5)/2 = (a + 2d + a + 4d)/2`

= `(2a + 6d)/2`

⇒ a + 3d

= a4 

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 9: Sequences and Series - Exercise [पृष्ठ १६४]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
पाठ 9 Sequences and Series
Exercise | Q 32 | पृष्ठ १६४

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

How many terms of the A.P.  -6 , `-11/2` , -5... are needed to give the sum –25?


If the sum of three numbers in A.P., is 24 and their product is 440, find the numbers.


A man deposited Rs 10000 in a bank at the rate of 5% simple interest annually. Find the amount in 15th year since he deposited the amount and also calculate the total amount after 20 years.


If the nth term an of a sequence is given by an = n2 − n + 1, write down its first five terms.


Show that the following sequence is an A.P. Also find the common difference and write 3 more terms in case.

−1, 1/4, 3/2, 11/4, ...


Find:

 10th term of the A.P. 1, 4, 7, 10, ...


Which term of the A.P. 3, 8, 13, ... is 248?


Which term of the A.P. 4, 9, 14, ... is 254?


Is 302 a term of the A.P. 3, 8, 13, ...?


Which term of the sequence 12 + 8i, 11 + 6i, 10 + 4i, ... is purely real ?


Which term of the sequence 12 + 8i, 11 + 6i, 10 + 4i, ... is purely imaginary?


The 10th and 18th terms of an A.P. are 41 and 73 respectively. Find 26th term.


In a certain A.P. the 24th term is twice the 10th term. Prove that the 72nd term is twice the 34th term.


Find the 12th term from the following arithmetic progression:

3, 8, 13, ..., 253


Find the second term and nth term of an A.P. whose 6th term is 12 and the 8th term is 22.


The sum of three numbers in A.P. is 12 and the sum of their cubes is 288. Find the numbers.


Show that the sum of all odd integers between 1 and 1000 which are divisible by 3 is 83667.


Solve: 

1 + 4 + 7 + 10 + ... + x = 590.


The first term of an A.P. is 2 and the last term is 50. The sum of all these terms is 442. Find the common difference.


If the 5th and 12th terms of an A.P. are 30 and 65 respectively, what is the sum of first 20 terms?


Find the sum of all two digit numbers which when divided by 4, yields 1 as remainder.


If the sum of a certain number of terms of the AP 25, 22, 19, ... is 116. Find the last term.


If the sum of n terms of an A.P. is nP + \[\frac{1}{2}\] n (n − 1) Q, where P and Q are constants, find the common difference.


If \[\frac{1}{a}, \frac{1}{b}, \frac{1}{c}\] are in A.P., prove that:

a (b +c), b (c + a), c (a +b) are in A.P.


If \[\frac{b + c}{a}, \frac{c + a}{b}, \frac{a + b}{c}\] are in A.P., prove that:

\[\frac{1}{a}, \frac{1}{b}, \frac{1}{c}\] are in A.P.


Insert five numbers between 8 and 26 such that the resulting sequence is an A.P.


A man is employed to count Rs 10710. He counts at the rate of Rs 180 per minute for half an hour. After this he counts at the rate of Rs 3 less every minute than the preceding minute. Find the time taken by him to count the entire amount.


We know that the sum of the interior angles of a triangle is 180°. Show that the sums of the interior angles of polygons with 3, 4, 5, 6, ... sides form an arithmetic progression. Find the sum of the interior angles for a 21 sided polygon.


A man saved ₹66000 in 20 years. In each succeeding year after the first year he saved ₹200 more than what he saved in the previous year. How much did he save in the first year?


The first and last terms of an A.P. are 1 and 11. If the sum of its terms is 36, then the number of terms will be


If the sum of first n even natural numbers is equal to k times the sum of first n odd natural numbers, then k =


Mark the correct alternative in the following question:

\[\text { If in an A . P } . S_n = n^2 q \text { and } S_m = m^2 q, \text { where } S_r \text{ denotes the sum of r terms of the A . P  . , then }S_q \text { equals }\]


Write the quadratic equation the arithmetic and geometric means of whose roots are Aand G respectively. 


If abc are in G.P. and a1/b1/y = c1/z, then xyz are in


Show that (x2 + xy + y2), (z2 + xz + x2) and (y2 + yz + z2) are consecutive terms of an A.P., if x, y and z are in A.P.


The fourth term of an A.P. is three times of the first term and the seventh term exceeds the twice of the third term by one, then the common difference of the progression is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×