Question

AP samantar shreni ka n va pad an= 3+4n.then find
Comman difference= ?​

Answer 1

EXPLANATION.

Ap = 3 + 4n.

→ Nth term of an Ap.

An = a + ( n - 1)d.

→ Let put n = 1

→ 3 + 4(1) = 7.

→ Let put n = 2.

→ 3 + 4(2) = 11.

→ Let put n = 3.

→ 3 + 4(3) = 15.

→ Let put n = 4.

→ 3 + 4(4) = 19.

Series are = 7,11,15,19.........

→ First term = a = 7.

→ Common difference = d = b - a = 11 - 7 = 4.

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More information.

(1) = Nth term of an Ap → An = a + ( n - 1 )d.

(2) = Sum of nth term of an Ap.

Sn = n/2 [ 2a + ( n - 1) d].

Answer 2

Question :-

If AP = 3 + 4n, Then find common difference.

Solution :-

To solve this question, we have to apply hit and trial method i.e. by substituting the value of n as 1,2,3 ...... and form a series.

After forming the series we can easily find the common difference of A.P.

Substituting n as 1 :

• 4n + 3 = 4 (1) + 3 = 7

Substituting n as 2 :-

• 4n + 3 = 4 (2) + 3 = 11

Substituting n as 3 :-

• 4n + 3 = 4 (3) + 3 = 15

Substituting n as 4 :-

• 4n + 3 = 4 (4) + 3 = 19

Substituting n as 5 :-

• 4n + 3 = 4 (5) + 3 = 23

So, we get a series as 7,11,15,19,23........

Common difference = 11 - 7 = 15 - 11 = 19 - 15 = 4

Hence, Common difference of A.P. = 4