1.3 nth term of an AP from the end
Let a be the first term and d be the
common difference of an AP having
mterms. Then, nth term from the end is (m – n + 1)th term from the beginning. So, nth term from the end is
T
m-n+1 = a + (m – n + 1 - 1)d = a + (m - n)d