The first and last terms of an AP are a and l repectively. Show that the sum of hte nth term from the beginning and the nth tern from the end is (a + 1).
Given, the first term, = a
Last term, = l
nth term from the beginning, an=a+(n−1)d
nth term from the end,tn=(I−(n−1)d)
Now, = [ a + (n – 1) d ] + [ l – (n – 1) d ]
= (a + l)