determine an ap whose third term is 9 and when fifth term is substracted from 8th term we get 6
Answers
Answer-------> 3 , 6 , 9 , .................................
Given------> Third term of an AP is 9 and when fifth term is subtracted from eighth term we get 6
To find-------> Determine AP.
Solution------> We know that,
aₙ = a + ( n - 1 ) d
Let , first term and common difference of AP is a and d .
ATQ, a₃ = 9
=> a + ( 3 - 1 ) d = 9
=> a + 2 d = 9 ..................( 1 )
ATQ, a₈ - a₅ = 6
=> a + ( 8 - 1 ) d - { a + ( 5 - 1 ) d } = 6
=> a + 7 d - ( a + 4d ) = 6
=> a + 7d - a - 4d = 6
=> 3 d = 6
=> d = 6 / 2
=> d = 3
Putting d = 3 in equation ( 1 ) .
a + 2 ( 3 ) = 9
=> a + 6 = 9
=> a = 9 - 6
=> a = 3
First term = a = 3
Second term = a + d
= 3 + 3
= 6
Third term = a₂ + d
= 6 + 3
= 9
So AP is ,
3 , 6 , 9 , ...........................
Answer:
RIGHT ANSWER IS 3,6,9
SO I LOVE U MY DARLING