if the seventh term of an AP is zero,prove that its 27th term is five times its eleventh term of class 10

1 answer

T7 = a+6d
T11 = a+10d
T27 = a+26d

a+6d = 0
a = -6d

T27 = -6d+26d = 20d
T11 = -6d+10d = 4d