Question

determine an A.P whose third term is 9 and fifth term is subtracted frm 8th term we get 6

Answer 1

Heya !!




3rd term = 9


a + 2d = 9 ---------(1)



And,




8th term - 5th term = 6


A + 7D - ( A + 4D ) = 6



A + 7D - A - 4D = 6




3D = 6


D = 6/3 = 2



Common difference ( D ) = 2




a + 2d = 9



a + 2 × 2 = 9



a = 9-4


a = 5



First term ( A ) = 5





Second term = A + D = 5 + 2 = 7



Third term = A + 2D = 5 + 2 × 2 = 9



Fourth term = A + 3D = 5 + 3 × 2 = 11



Hence,



AP = 5 , 7 , 9 , 11......

Answer 2

we find the common difference first and then put the value in the equation we created by the third term..