Question

If 5 times the fifth term of an AP is equal to 8 times the eighth term show that its 13th term is zero

Answer 1

Answer:

let of the AP

first term= a

common difference=d

ATQ

5[a+(5-1)d]=8[a+(8-1)d]

5(a+4d)=8(a+7d)

5a + 20d = 8a + 56d

3a = 36d

a= -12d

Now 13th term

a+(13-1)d

=-12d+12d

=0

(proved)

Step-by-step explanation:

Answer 2

Answer:

If five times the fifth term of an A.P is equal to eight times its eighth term, show that its 13th term is zero. If five times the fifth term of an A.P is equal to eight times its eighth term, show that its 13th term is zero.