Question

if tn is the nth term of an A.P then the value of tn+1 - tn-1 is?

Answer 1

Answer:

2d

Step-by-step explanation:

well let's break it down this way,

tn= a+(n-1)d

so, t(n-1)=a+[(n-1)-1]d ......1

and,

t(n+1)=a+[(n+1)-1]d ......2

so by 1 and 2

tn+1 - tn-1 = {a+(n)d} - {a+(n-2)d}

=> nd - (n-2)d = 2d