Answer;
Now we have to calculate a
Putting d =-1 in (2)
a + (n-1) d =m
a + (n-1) x (-1) = m
a-n+1= m
a= m +n-1
For ph term,
we use the formula,
a, =a+ (n-1)d
putting n =p, d= -1 and a = m +n-1
a, = (m +n-1) + (p-1) (-1)
= m +n-1+(-p+ 1)
= m +n-1-p+1
= m +n-p
Thus, pih term = m +n-p