Question

If 4 time the 4th term of an AP is equal to 9 time the 9th term of an AP what is 13 times the 13th term of this AP​

Answer 1

Answer:

0

Step-by-step explanation:

Let first term of A.P is a and common difference between terms is d.

If an=nth term of AP=a+(n-1)d

then a4=a+(4-1)d=a+3d

and a9=a+(9-1)d=a+8d

Given 4×a4=9×a9,

4(a+3d)=9×(a+8d)

4a+12d=9a+72d

5a+60d=0

a+12d=0

a+(13-1)d=0

a13=0

So, 13×a13=13×0=0