Question

किसी A.P. का 8वाँ पर 37 तथा 12वीं फ 57 है। A.P. को ज्ञात करें।

Answer 1

Step-by-step explanation:

let first term of an A.P. is a and common difference is d

so,

a + 7d = 37 :- 1

&

a + 11d = 57 :-2

subtracting equation 1 & 2 , we get

a + 7d = 37

a + 11d = 57

- - -

or, -4d = -20

hence, d= 5

putting the value of d in equation 1, we get

a + 7 × 5 = 37

or, a + 35 = 37

hence, a = 37 - 35

= 2

A.P. = 2 , 7 , 12 , 17.........