Question

explain formula TN=A+(N-1)D

Answer 1

Answer:

Step-by-step explanation:

it means tn is equal to a(first term)added to the product of n-1 and d (common difference)

take for example the AP 2, 4, 6, 8……10terms

ten a = 2

d=2

n=10

then tn=a+(n-1)d

tn=2+(10–1)2

tn=2+9(2)

tn =2+18

tn=20

Thnx . I hope u like my Ans.

Answer 2

Answer:

The characteristic feature of arithmetic progression is a common difference (D)

say the first term is "A"

second term is A+D

third term is A+2D

and so on

we now observe that for the Nth term(TN),((N-1)×D) is added to A

thus, we get the formula TN= A+(N-1)D

eg1:

12, 15, 18.......

find the 50th term

TN= A+(N-1)D

D= +3, A=12

therefore, 12+((50-1)×3)= 153

eg2:

100,94,88.......

find the number of terms if the nth term is -44

TN= A+(N-1)D

D=-6, A=100

N= ((-44-100)/-6)+1

=25