Class 11

Math

Algebra

Sequences and Series

The geometric mean between 4 and $41 $ is

Connecting you to a tutor in 60 seconds.

Get answers to your doubts.

Which of the following list of numbers does form an AP? If they form an AP. write the next two terms :(i) 4, 10, 16. 22, . . .(ii) 1,-1, -3,-5, . . .(iii) -2,2,-2,2, . . .(iv)1,1,1,2,2,2,3,3,3, . . .

The Fibonacci sequence is defined by $1=a_{1}=a_{2}$ and $a_{n}=a_{n−1}+a_{n−2},n>2$. Find $a_{n}a_{n+1} ,$for n = 1, 2, 3, 4, 5.

Find the $11_{th}$from the last term (towards the first term) of the AP : $10,7,4,˙˙˙,62.$

If a, b, c are in A.P., b, c, d are in G.P. and $c1 ,d1 ,e1 $are in A.P. prove that a, c, e are in G.P.

Find the sum of the products of the corresponding terms of the sequences 2,4, 8, 16, 32 and 128, 32, 8, 2, $21 $.

Write the first three terms in each of the following sequences defined by the following:(i) $a_{n}=2n+5$ (ii) $a_{n}=4n−3 $

Find the sum of the sequence 7, 77, 777, 7777, . . . to n terms.

Write the first five terms of the sequence whose $n_{th}$terms are : $a_{n}=n(n+2)$