Question

if twice the second term of an ap is equal to 5 times the 5th term of the AP show that seven term is zero​

Answer 1

Answer:

formula of ap is a+(n-1)d

let twice the second term of an ap be x2

x2=a+d

x2=5(x5)

2(a+d)=5(a+4d)

x5 is the 5th term of ap

2a+2d=5a+20d

-3a=18d

a= -6d

x7 is seventh termin ap

a+6d

-6d+6d=0

proved